Moodle in English: Site only accessible by IP, not domain name temporarily

I'm having a strange problem.

What's happening? The moodle site goes time out when accessed by domain name while at the same time accessible via IP (changing wwwroot in config.php) on certain parts of the day. I am not a system admin but I'm trying to find out what's the issue. This is happening on certain days of the week and certain parts of the day.

What I've done so far? I have changed the DocumentRoot in apache config file to "a new folder" having a simple index.html and strangely it works. I can see the index.html via domain name. So the issue is not the domain name resolution or apache not loading the contents of DocumentRoot.

Second, I've also tried viewing the apache status (mod_status) at the same time and it appears that apache is responding to requests (all R,W,K flags) with CPU load below 35%.

What makes me pull my hairs is that this whole thing "magically" becomes normal after a few minutes or 1-2 hours and then for the rest of the day, the moodle site is working flawlessly.

So, I don't know what to look for or how to debug this issue. Any pointers?

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Re: Site only accessible by IP, not domain name temporarily

by Visvanath Ratnaweera - Wednesday, 7 April 2021, 3:24 PM

Very puzzling. Are you sure, you have the literal domain URL in $CFG->wwwroot, no PHP magic? And the protocol, HTTP or HTTPS, is always the same? Do you know whether the server is behind a reverse proxy, or if it is Nginx, it is configured properly? See https://docs.moodle.org/38/en/Nginx. Does this happen from one network / one person, or does this happen to everybody?

Any connection to your previous problem: https://moodle.org/mod/forum/discuss.php?d=402417#p1636943, like the cron job struggling with PDF conversions or filling up temp directories?

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Re: Site only accessible by IP, not domain name temporarily

by Najam Fazal - Wednesday, 7 April 2021, 5:38 PM

A few details:

$CFG->wwwroot = 'https://mydomain.com'
Server: Apache 2.4, not NGINX. No proxy.
Always HTTPS. All HTTP requests are redirected to HTTPS. Certifcate config by LetsEncrypt. Standard config.
Happens everywhere
Allowed ICMP in firewall, pinged, got successful response
Curl to domain (from the server and my PC) returned HTML response
The temp directory, I didn't check. Referred issue was a different story. Currently, have ample free storage (over 300 GB)

Is there any command (run on server) or utility that can help me go through the whole request flow like when a request was made to mydomain.com and then how apache resolves it to document root and subsequently how moodle loads the page. Or what to look in apache conf during the downtime to figure out what is causing the issue?

Its definitely something that's messing up moodle code (since the document root to other folder works fine). Is there anything to patch in the code that verifies this? Or look for any user activity that's causing it. I will also extract the logs (apache + moodle) up to the point where the server stops responding via domain to see it leads to anything.

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Re: Site only accessible by IP, not domain name temporarily

by Visvanath Ratnaweera - Wednesday, 7 April 2021, 9:06 PM

The tool to see where it went wrong and why is https://docs.moodle.org/38/en/Debugging. Raise the level to DEVELOPER. No point it sending the trace to the browser, let it just send to the web servers logs.

Ideally you let a monitoring program like Munin record all aspects of the server and look for anomalies when this happens. You could run something like the Unix top and watch it during the hiccups, but you have to be there, ready.

What is the state of the code? Anything changed? Try 'git status'. Is the code tree writable by the web server? Any odd time stamps?

Is your database server in the same machine, dedicated to Moodle, or you Moodle is configured to use a database server somewhere else?

More likely is a network issue. Is anything, code or the data directory network mounted? Any recurring heavy loads on the server? How often is your cron.php run? Any conjestion in the ad-hoc task list?

Finally, talk to the whole IT team, not only the server administrator. The people who run the whole server infrastructure, the network team, ...

P.S. If you've solved your previous problem https://moodle.org/mod/forum/discuss.php?d=402417#p1636943, put a note there saying how and mark closed. People have taken trouble to help you, it is not nice to say nothing.

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Re: Site only accessible by IP, not domain name temporarily

by Ken Task - Wednesday, 7 April 2021, 10:08 PM

Is this server in a VM? (Virtualbox/VMWare/Other)

Have any additional protections ... like mod_security or other active?

'certain parts of the day' ... can you be more exacting ... like from 1:00PM to 3:00PM on Mon., Wed.?

What DNS server is authoratative for your Top Level domain? External DNS as well as Internal DNS.

In your server's OS, assuming linux here, what DNS servers are being used for resolving ... /etc/resolv.conf in many Linux boxen.

Sounds like a networking issue ... not moodle as it's dynamic only in content not networking.

IF server is internal to a private network and wired to a switch what of the port on the switch or switch itself? traceroute to the internal gateway IP looks like?

ssh into server as root and issue:

ifconfig

looking for the IP address by which server is accessible and RX/TX lines that show packet errors

Looking for something like this:

        RX packets 3458770 bytes 2586216129 (2.4 GiB)
        RX errors 0 dropped 0 overruns 0 frame 0
        TX packets 3770430 bytes 1078858871 (1.0 GiB)
        TX errors 0 dropped 0 overruns 0 carrier 0 collisions 0

'SoS', Ken

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Re: Site only accessible by IP, not domain name temporarily

by Najam Fazal - Thursday, 8 April 2021, 2:45 AM

I feel ashamed of sharing very less information, thanks to Moodle Gurus (Ken and Visvanath) for your pointers. So here it is:

Machine Info: Single VM Moodle. MySQL, Apache and File Storage all on one VM. Ubuntu 18. Intel Xeon 2 vCPU, 8 GB RAM
Network: Public cloud. Internal networking managed by cloud provider, no control over it. No private subnets or VPC defined by us.
CPU Load: For past 1 week is attached
Cron Frequency: Runs every minute. Checked status of task “regular completion data” that runs every minute and it shows “success” for the entire duration of downtime today (Wed 7-Apr 10am to 11am). Almost all ran for 0.01 sec, 6 reads, 0 writes, used 6 dbqueries.
Moodle Version: 3.8
Congestion in Adhoc Tasks: In Moodle, filtered task logs by adhoc and found them successfully running before and after downtime. No adhoc task ran during the downtime or just before or after that but this may be due to the scheduled time.
Moodle Debugging: Can’t access the site at downtime so don’t know what and how to see that
Unix Top: Ran at downtime. Showed usual CPU and mem usage. Nothing overloading or 100% CPU. Various apache processes and mysql.
Code Tree Changes: git status returned a lot of files modified but I am sure that's because of permission changes. Didn't run diff though. Yes, all the files has 755 and writeable by the server. No files have been modified in the past few months.
Mod Security: None that I know. How can I find it out? No setting in vhost config file.
Issue Occurrence Frequency (Times): Between 10 am to 11 am and sometimes up till noon. This (10 am to noon) is peak time. Sometimes in evening around 7 pm but for short duration (< 30 mins).
Issue Occurrence Frequency (Days): That’s tricky because this week it happened on Tue and Wed. Last week on Mon and Wed. A week before that on Tue and Fri
DNS Authority: Based on this SO answer, see responses in attached terminal.txt that I ran through nslookup on my PC for the domain (and sub-domain that the moodle site is on). I don’t understand external or internal DNS so please if you can clarify that.
Server's Resolver: See attached terminal.txt file
Trace Route: See attached terminal.txt file
ifconfig: See attached terminal.txt file

Let me know if anything else that I need to look for. Meanwhile I will try to install Munin and share the findings. I don't understand it is a simple and standard install that we do everywhere and even several other moodle are running with the same cloud provider in the same region with similar VM configs.

I will re-run the commands (ifconfig, DNS and trace route) during the next downtime (praying it will never ever occur on peak times) and report back.

If there's any other thing I need to check or do, please let me know. BIG thanks to you guys!!

P.S. (For Visvanath): That issue didn't resolve. The client later managed the storage on their own so I didn't follow it up.

Terminal.txt

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Re: Site only accessible by IP, not domain name temporarily

by Ken Task - Thursday, 8 April 2021, 3:41 AM

Sent you a PM ... please respond there in PM as info asked is kinda private.

Concept: networking comes before application - application here is your web server and specifically moodle. I don't think the issue is with your Moodle nor it's config, but rather, networking/DNS.

Discovering where is rather difficult in that you or others have access to the end points, but NOT all that is in between - workstation (PC/Windows) and server on another remote network (Linux).

ifconfig on server did not show any dropped packets for RX/TX.

On your server you wouldn't see any entries in web servers access logs or error logs from your workstation (public IP) IF .... IF ... IF ... no traffic is reaching your server.

Your traceroute from PC to Server shows 36 hops???!!!! and while the clip shared did show it supposedly reached ... can see some rather strange routing .... -> public_ip -> private IP (192.168.x.x) to a larger private IP network on 10.253.4.x then routed back to public IP's.

hops:

1     3 ms     1 ms     1 ms 192.168.18.1 <--- (My Router's Default Gateway)
2     9 ms     4 ms     4 ms 202.163.100.245
3     6 ms     5 ms     7 ms 202.163.100.105
4     *        9 ms     *     202.163.100.121
5     4 ms     4 ms     6 ms 192.168.117.18
6     5 ms     5 ms     5 ms 192.168.100.21
7     6 ms     7 ms     9 ms 10.253.4.50
8    12 ms     8 ms    10 ms 10.253.4.4

DNS

primary name server = nsg1.namebrightdns.com for the FQDN of the moodle server seen/shared in terminal.txt file

dig @nsg1.namebrightdns.com moodle.x.x

shows

;; QUESTION SECTION:
;moodle.x.x. IN A

but no response

Also a reverse lookup on the public IP (IPv4) of your moodle server ... if response to me was correct:

dig -x IP#.IP#.IP#.IP#

QUERY: 1, ANSWER: 0, AUTHORITY: 1, ADDITIONAL: 1

note no answer above

There should be some reverse ... maybe not for your registered TLD .. but a reverse for your providers IPv4's at least.

Now what to do ... talk to any/all networking entries involved beginning with your provider to internet (ie, Windows) -> Internet.

Ask helpdesk of where you host to provide networking/DNS info from the perspective of your moodle server.

'SoS', Ken

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Re: Site only accessible by IP, not domain name temporarily

by Ken Task - Thursday, 8 April 2021, 5:22 AM

Follow up ... now that I have the true FQDN of the server! ...

CloudFlare issue?

dig -x ontrueIPv4address of server

shows:

;; AUTHORITY SECTION:

ben.ns.cloudflare.com

So you do have 'protections' ... via CloudFlare - which is not only a content delivery network but also a 'protective' service for your true server - whose IP address does show to be on Amazon's network.

Advise contacting CloudFlare support 1st then Amazon support.

'SoS', Ken

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Re: Site only accessible by IP, not domain name temporarily

by Najam Fazal - Thursday, 8 April 2021, 6:24 AM

Thanks Ken for your support and guidelines. I will contact the domain registrar and forward these details to see if leads to the resolution.

Big thanks to you and Visvanath.

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Re: Site only accessible by IP, not domain name temporarily

by Visvanath Ratnaweera - Thursday, 8 April 2021, 1:36 PM

Hi

My number one suspicion is a network issue. Ken is on to something. Your IT staff need to take over - it is not a Moodle issue.

In the meantime, some clarifications on Moodle:

> CPU Load: For past 1 week is attached

The site is indeed a busy one, there are regular (daily?) peaks of 40-70%. Still withing limits but the vertical climb is unusual. Are you sure that this is a flood of Moodle users, or is it a background task, like automatic course backups?

> Moodle Debugging: Can’t access the site at downtime so don’t know what and how to see that

https://docs.moodle.org/38/en/Debugging#In_config.php. No display will send the trace to the web server logs.

Note that this effects the performance. So change shortly before the expected time and undo.

If the logs stop during the blockade, that indicates no requests reach the web server. So the cause is before that. You can check the logs even now, without the debugging and waiting for the next blockade.

> Issue Occurrence Frequency (Times): Between 10 am to 11 am and sometimes up till noon. This (10 am to noon) is peak time. Sometimes in evening around 7 pm but for short duration (< 30 mins).

If the vertical rise of load is also at 10 am, there is some connection. See my note above on the CPU load.

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Re: Site only accessible by IP, not domain name temporarily

by Najam Fazal - Thursday, 8 April 2021, 3:40 PM

CPU Load: Yes it's normal. It is when most users have their sessions so they all login and join the session in bulk. At times it happened in the past that the staff took backups which causes server to halt but that is not the case in these two weeks.

I'll try debugging too. Forwarded to the network and domain registration people. I will update any leads here.

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Re: Site only accessible by IP, not domain name temporarily

by Visvanath Ratnaweera - Thursday, 8 April 2021, 4:27 PM

I'm still curious.

CPU Load: The time scale of the graph is rough. But to me it looks like a large number of users join within a minute. You said, your VM is 2 vCPU, 8 GB. What is the number of active students? How many join withing the same minute? What do they do right after joining, starting a full on-line exam (quiz)?

It is painful to take course backups interactively, definitely not during the peak hours! See https://docs.moodle.org/en/Automated_course_backup.

> Network: Public cloud. Internal networking managed by cloud provider, no control over it. No private subnets or VPC defined by us.

I don't know what a "public cloud" means or how a different party maintain the server room network. Whatever, if you (and Ken) suspect Cloudflare is at the center of this puzzle, why don't you deactivate it and compare?

Edit: Saw https://moodle.org/mod/forum/discuss.php?d=420661#p1695423 after writing this post. If Cloudflare interferes that aggressively, don't ask Moodle for explanations!

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Re: Site only accessible by IP, not domain name temporarily

by Najam Fazal - Thursday, 8 April 2021, 5:11 PM

Yes that's right. Around 150 to 250 students join within like 3-4 minutes depending on their classes. The graph above is 5 min aggregated. So imagine kids rushing to classes from an assembly hall. It is normal and in fact usually happens since the very start and never caused any issue on this machine. It made an impact when we were using a smaller machine earlier but not with this one.

By public cloud I mean Azure, AWS and GCP and we don't have set out own private network per se. The default private network, internal network, gateway and virtualization is pre-managed and we don't have any control or say in that, in fact we don't have to care about that.

I don't understand one thing, you and Ken saying its networking issue but how come changing the DocumentRoot in apache config to a different folder (that contains only index.html) loads perfectly fine via URL? I am definitely missing something here.

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Re: Site only accessible by IP, not domain name temporarily

by Ken Task - Thursday, 8 April 2021, 10:25 PM

When you change document root, apache has to be restarted. Caching no longer in affect as that was your moodle. A simple index.html doesn't do any query of any backend DB to acquire data to ship to your brower.

With CloudFlare in-between, as it would be with DNS, that would be cached by CF and that access (index.html is what ... 1K at the most?) should be extremely fast - would imagine all of your Moodle users could access that static html page at the same time! Remember though, that access would stop at CF and be returned to all the clients accessing ... would never reach your Moodle server on Amazon.

So when you do that test of switching document root, what do you use as a URL in the browser you are using? https://IP/ or https://FQDN/

iP would attempt going directly to Amazon ... FQDN would run through CloudFlare ... never reach your Amazon server and what you get back is the cached page from CF's content delivery caching.

In order to test if it's CF issue, is to change DNS such that your FQDN doesn't return a CF route but the true Amazon IP of your web service. CF then taken out of the path to your Moodle. That kinda change would/might take a while for the DNS change to get refreshed in DNS servers.

Your moodle has a config.php file. One of the requirements of that file and clean interaction with your moodle, is the $CFG->wwwroot value ... a URL.

Moodle doesn't like relative addressing ... matterof fact the above value is used to record rows in tables of your DB to local (to your Moodle) resources ... like admin links.

In all of this, you've not really shared any info about DB server. Is that localhost in your config.php file or is it a DB server in Amazon's network?

And since a database is involved with Moodle, have you ever tweaked any DB server settings? Typical adjustments on a standalone ... meaning any/all of anything releated to moodle is on the same server (not split) ... are

skip-name-resolve
innodb_buffer_pool_size
innodb_buffer_pool_instances

max_allowed_packet

Don't ask what those valuies should be with your really un-known setup.

Suggest installing MySQLTuner.PL on web server and run it from there to see what recommendations it might have for tweaking.

Just now I did a traceroute from my location to your Moodle server. Once by IP and once by FQDN.

In both they get to a hop on 52.94.35.x which goes to 52.94.33.x on the Amazon's network.

A cliip:

15 * * *
16 52.94.35.91 (52.94.35.91) 138.250 ms
    52.94.35.83 (52.94.35.83) 142.833 ms
    52.94.35.121 (52.94.35.121) 131.800 ms
17 52.94.35.64 (52.94.35.64) 129.890 ms
    52.94.35.116 (52.94.35.116) 127.939 ms
    52.94.35.110 (52.94.35.110) 130.474 ms
18 52.94.33.173 (52.94.33.173) 127.359 ms 127.290 ms
    52.94.33.167 (52.94.33.167) 138.500 ms
19 52.94.33.2 (52.94.33.2) 130.340 ms
    52.94.33.14 (52.94.33.14) 130.810 ms
    52.94.33.2 (52.94.33.2) 130.543 ms

The ms times expected as am in SA USA. but speed is of the essence, yes?

If you note, at every hop there is at least 2 IP addresses involved and those ms times add up. AWS Dogfish Routing?

'SoS', Ken

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Re: Site only accessible by IP, not domain name temporarily

by Ken Task - Friday, 9 April 2021, 1:52 AM

Follow up and checks from my connections to internet ...

DNS is now changed ... learn.x.x points directly to your Amazon ... no CloudFlare involved now.

Curl test from cli ... curl -I https://IP address

curl: (60) SSL: no alternative certificate subject name matches target host name 'Amazon IP'
More details here: https://curl.haxx.se/docs/sslcerts.html

curl failed to verify the legitimacy of the server and therefore could not
establish a secure connection to it. To learn more about this situation and
how to fix it, please visit the web page mentioned above.

Probably need to setup web service so that any attempts to access flip to https://FQDN/ ... same as wwwroot in config.php of Moodle.

curl -I https://FQDN/ does respond as it should.

Suggest you do a traceroute from your workstation without -n 50 .. default hops should be 30 then ... to see if number of hops to your moodle is now fewer. Obviously, the fewer the hops the better.

BTW, my trace is coming from USA and thus not a good test for your server.

Would assume most if not all of your students/faculty connections to internet would be closer if Amazon has your server in an Amazon data center close to you.

https://aws.amazon.com/about-aws/global-infrastructure/

'SoS', Ken

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Re: Site only accessible by IP, not domain name temporarily

by Ken Task - Friday, 9 April 2021, 3:15 AM

Another follow up ... as I re-read ...

"Single VM Moodle. MySQL, Apache and File Storage all on one VM Ubuntu"

Memory? With such a server, it's a balancing act between apache and MySQL. That's why the suggestion to install MySQLTuner and run it.

Important info from MySQLTuner ...example ... from an all in one 8 Gig server.

[--] Physical Memory : 7.6G
[--] Max MySQL memory : 2.2G
[--] Other process memory: 402.5M

[OK] Maximum reached memory usage: 2.0G (26.81% of installed RAM)
[OK] Maximum possible memory usage: 2.2G (28.90% of installed RAM)
[OK] Overall possible memory usage with other process is compatible with memory available

Another tool which may or may not provide useful info ... apache2buddy.

Example clipped output from same 8 Gig server

[ -- ] Your PHP Memory Limit (Per-Process) is 128M.
[ -- ] MySQL Detected => Using 1232.57 MB of memory

[ -- ] httpd is currently using 322.31 MB of memory.
[ -- ] The smallest apache process is using 21.05 MB of memory
[ -- ] The average apache process is using 21.41 MB of memory
[ -- ] The largest apache process is using 21.91 MB of memory

Many moodles begin their life as a single/standalone. And need to tweak settings for MySQL and Apache (depending upon how running).

Eventually, due to usage and performance, the next logical step is to break apart DB server to a dedicated DB server whose memory could be for all of the DB ... the more MySQL can fit into memory the less I/O and faster the DB is.

If one were to be logged onto server via ssh at the time of peak usage and running top, you get realtime usage. Bet MySQL on your server stays at the top of top. top command, BTW, also shows % Memory used as well as SWAP space. Uhhhh ... SWAP space for your DB is not good ... that means disk I/O!

Anyway ... you've got some checking to do!

'SoS', Ken

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Re: Site only accessible by IP, not domain name temporarily

by Visvanath Ratnaweera - Friday, 9 April 2021, 3:46 AM

Ken, I know it's a pending investigation. But what is the charge for now? That the VM is too weak for / not capable of handling the surge at 10 am? Even Cloudflare can not save it? Or, perhaps CF is worsening the situation? I am thinking of the convoluted network route.

Dumb question: The "VM" is on AWS. Is it not supposed to auto-scale?

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Re: Site only accessible by IP, not domain name temporarily

by Ken Task - Friday, 9 April 2021, 4:49 AM

More investigation required by OP ... only so much one can do remotely and without access.

Truth .. I mistakenly used OP's sub for true FQDN .. which is NOT moodle.mysite.com and because that TLD is real and happens to be hosted with a different provider went down a rabbit hole ... very deep. So all the previous info shared about discovery not correct. My fault .... should never take info shared literally! :|

A VM single server (standalone) with any provider .. Rackspace/Google Compute Engine/Amazon ... is similar, however, Amazon I thought did have the ability to be 'burstable' .... autoscale upwards ...

https://aws.amazon.com/autoscaling/

From above ... ".... it’s easy to setup application scaling for multiple resources across multiple services in minutes...." Hmmmm where have I seen 'easy to setup' before ... uhhhhh, every provider! :\

Don't know that OP needs or not but from what was described - 400 users hitting site at one time? .... could be.

CloudFlare ... these forums are behind cloudflare. Ever see that 'Oops! Something has gone wrong with the Internet!' ... blah, blah, blah, error screen when attempting to get to this site?

CF started as security and in their pursuit of that discovered caching was a plus.

I've never had a CF in front of a Moodle but can see it adds a layer of complexity. Great when it works ... sucks when it doesn't! :| And it does require trouble shooting approaches that are different.

Sooooo .... we wait!

'SoS', Ken

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Re: Site only accessible by IP, not domain name temporarily

by Najam Fazal - Friday, 9 April 2021, 2:14 PM

Updates since Wednesday and Now:

From end user's perspective. No issue has been faced (very strange) till now Fri 11 am.
Currently around 260+ users since past 1 hour
At target time (10-12), remember no downtime yet:
- Checked ifconfig for packet loss. Nothing lost.
- Checked tracert from two separate network ISP. Got 36 hops. Tracert n30 doesn't reach my IP.
- Checked through nslookup, dig. Apparently the DNS values are the same.
- Checked top, htop: CPU usage pretty usual goes up and down but not like 100% (or even 80%) for like 5 minutes straight (not even for a min) or Mem blockage. Free mem around 300-500 MB
- Yes there was a slowness I observed during this peak yesterday and (for a bit) today.
- Regarding slowness, (tested just at the time of writing this)
  - Chrome dev tools show a "Stall" on /my (dashboard) for 3.5 secs and then the rest of the page loads like a jiffy.
  - Again Firefox dev tools shows a "Blocked" for 9.91s and TLS Setup at 9.76s (See image)
  - Mod_status showing 110-130 requests (~6-8 requests/sec) with most R, K and DOT(.) flags

The following is just 5 mins earlier,

Apparently, for now, everything is working (me pulling my hair). Why? and more importantly how?

@Ken if you want direct access, I can give you privately.

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Re: Site only accessible by IP, not domain name temporarily

by Ken Task - Saturday, 10 April 2021, 5:13 AM

Interesting ... lib/babel-polyfill/polyfill.min.js is blocked!!!!!

Think we asked before but will again ... on learn server do you have any web application firewall running?

What is default theme?

'SoS', Ken

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Re: Site only accessible by IP, not domain name temporarily

by Najam Fazal - Saturday, 10 April 2021, 6:52 AM

Application firewall, I don't think so. Default theme: Moove

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Re: Site only accessible by IP, not domain name temporarily

by Ken Task - Saturday, 10 April 2021, 6:39 AM

From viewing the default login page of https://learn.tld.org/

theme_moove

https://moodle.org/plugins/theme_moove/versions

require(["media_videojs/loader"], function(loader) {
loader.setUp(function(videojs) {
videojs.options.flash.swf = "https://learn.tld.org/media/player/videojs/videojs/video-js.swf

swf = shockwave flash.
https://helpx.adobe.com/shockwave/shockwave-end-of-life-faq.html

Themes with issues can and do wrek havoc on a site in ways that are strange and unknown.

Is there supposed to be something swf on the front page/login page?

Got your PM and server info - thanks - but before I do anything, check theme.

'SoS', Ken

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Re: Site only accessible by IP, not domain name temporarily

by Najam Fazal - Saturday, 10 April 2021, 7:38 AM

"Is there supposed to be something swf on the front page/login page?"

No. Not at all.

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Re: Site only accessible by IP, not domain name temporarily

by Visvanath Ratnaweera - Friday, 9 April 2021, 3:47 PM

Yes, more investigation required by OP.

The confusion with "mysite": That is why there is an example.com (others, ref. https://en.wikipedia.org/wiki/Example.com). I have heard stores of people who grabbed such domains and collected interesting e-mails.

OP just reported that the service is unbroken today https://moodle.org/mod/forum/discuss.php?d=420622#p1695629. Has nothing changed? I thought you changed the site's DNS.

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Re: Site only accessible by IP, not domain name temporarily

by Najam Fazal - Friday, 9 April 2021, 2:28 PM

VM's too weak? For now, it doesn't show in terms of handling requests to an end user. However, we are up for auto-scaling. But the issue is FQDN access here as I understand. Does CF starts blocking requests coming from different IPs for a specific IP within a short timespan (say 3-4 mins in our case where students rushing in) but even if that's the case, it also happens around 8 am too but then it doesn't happen.

For VM, we'd separate them out tonight to a separate DB and webserver to see if it is something caused by many users logging in. Though we don't see any mem issues. Here's a recent htop output around 11 am:

Perhaps should we change the MaxRequest and max connection settings on apache and mysql? Any thoughts?

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Re: Site only accessible by IP, not domain name temporarily

by Ken Task - Friday, 9 April 2021, 11:08 PM

Did you happen to run htop before you split DB server from Web server?

I see an 8 Gig server.

In config.php of moodle code is the DB server using an FQDN or an IP address?

Have you installed and run MySQLTuner ... on web server as well as on dedicated DB server? Reason for both ... from Web server involves network. From dedicated DB server no network.

How about apache2buddy on web server?

And in /etc/resolv.conf (what DNS servers is your Web server using to make DNS queries?

'SoS', Ken

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Re: Site only accessible by IP, not domain name temporarily

by Najam Fazal - Saturday, 10 April 2021, 1:18 AM

No, I didn't split the DB and webserver. Should I do it? I will install MySQL Tuner, Apache2buddy and Munin tonight.

/etc/resolv.conf has the following:

nameserver 127.0.0.53

options edns0

search eu-west-2.compute.internal

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Re: Site only accessible by IP, not domain name temporarily

by Ken Task - Saturday, 10 April 2021, 2:14 AM

"No, I didn't split the DB and webserver" ... thought you said you did!!! :|

No don't split right now ... not until you see MySQLTuner and Apache2buddy runs.

That name server is a loop back ... on local server 127.0.0.x is local.

Ahhh .... but note that search parameter does show to use an .internal (not public DNS) at eu-west-2 for resolutions.

So, from ssh into your server do some DNS dig queries like I have shown only point the DNS server @ eu-west-2.compute.internal

dig @eu-west-2.compute.internal learn.tld.org

We should see an Amazon IP for learn.tld.org.

Please note: I do not host with Amazon ... just providing suggestions without true first hand knowledge of hosting there.

And another .... in what Amazon data center is your server. Would hope the one closest to you and all your clients. The DNS server FQDN shows a long hop (or mutiple hops) to eu-west-2 ... Europe/West. Wonder what a traceroute from your server to eu-west-2.compute.internal looks like

traceroute eu-west-2.compute.internal

Assuming your server is allowed to do traceroutes. If not, how about a constant ping: ping eu-west-2.compute.internal ... [Cntrl][c] to cancel.

We might be getting closer to issue ... dunno for sure! :|

'SoS', Ken

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Re: Site only accessible by IP, not domain name temporarily

by Najam Fazal - Saturday, 10 April 2021, 3:21 AM

From server:

# dig @eu-west-2.compute.internal learn.tld.org

dig: couldn't get address for 'eu-west-2.compute.internal': not found

# traceroute eu-west-2.compute.internal

eu-west-2.compute.internal: No address associated with hostname

Cannot handle "host" cmdline arg `eu-west-2.compute.internal' on position 1 (argc 1)

# ping eu-west-2.compute.internal

ping: eu-west-2.compute.internal: No address associated with hostname

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Re: Site only accessible by IP, not domain name temporarily

by Ken Task - Saturday, 10 April 2021, 4:56 AM

Like I've confessed before (truth in assisting), I have never hosted with Amazon and have not had access to an Amazon server ... just suggesting things to try/check seeking resolution to the described problem.

Think about it ... if this:

dig @eu-west-2.compute.internal learn.tld.org

dig: couldn't get address for 'eu-west-2.compute.internal': not found

failed with not found, traceroute and ping won't work either! But thanks for verifying that!

Now the question is how did that parameter (search) in the setup of DNS on your server get there. In all my years of hosting (a box I build in a private network - am the DNS servers admin) or as a customer on RackSpace or Google Compute Engine (where I am NOT the DNS servers admin and have to use whatever provider provides), I've never really seen any of those pointed to a .internal FQDN for DNS search.

Amazon does have a service just for DNS ... Route 53 (port 53 is usually default port for BIND DNS servers, thus the name including 53).

Please see and read:

https://docs.aws.amazon.com/Route53/latest/DeveloperGuide/resolver.html

I'd rate that page as 'not helpful' at all ... but that's me .... it's a really DEEP DEEP dive into DNS on Amazon's network.

Here's Moodle's official docs on how to setup a moodle on Amazon ..

https://docs.moodle.org/310/en/Installation_Guide_for_Installing_on_Amazon_EC2

no where in there do they mention DNS, but we know DNS must work!

Got one of these?

https://aws.amazon.com/console/

See any DNS icons in that?

They do offer training:

https://aws.amazon.com/training/digital/

https://aws.amazon.com/premiumsupport/knowledge-center/ec2-static-dns-ubuntu-debian/

Now am NOT saying do what it says in the link below, but do investigate if you have those config file it shows:

https://aws.amazon.com/premiumsupport/knowledge-center/dns-resolution-failures-ec2-linux/

Now if some other consultant set all that up for you to use, contact consultant! Get your $$$'s worth out of them!

'SoS', Ken

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Re: Site only accessible by IP, not domain name temporarily

by Najam Fazal - Saturday, 10 April 2021, 6:49 AM

Actually each Amazon EC2 instance has public and private DNS which is made up of:

For Public: ec2-<PublicIP>.<aws-region-shortname>.computer.amazonaws.com

For Private: ip-<PrivateIP>.eu-west-2.compute.internal

So for my server, it is:

ec2-PubIP-PubIP-PubIP-PubIP.eu-west-2.compute.amazonaws.com

ip-PrvIP-PrvIP-PrvIP-PrvIP.eu-west-2.compute.internal

PM you public and private IPs

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Re: Site only accessible by IP, not domain name temporarily

by Najam Fazal - Saturday, 10 April 2021, 3:27 AM

The Amazon region is London and has the lowest latency (~120ms) from the list of possible regions given to us. However, most of the users comes from South Asia.

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Re: Site only accessible by IP, not domain name temporarily

by Najam Fazal - Saturday, 10 April 2021, 3:29 AM

From server:

# dig eu-west-2.compute.internal

; <<>> DiG 9.11.3-1ubuntu1.14-Ubuntu <<>> eu-west-2.compute.internal
;; global options: +cmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 17166
;; flags: qr rd ra; QUERY: 1, ANSWER: 0, AUTHORITY: 0, ADDITIONAL: 1

;; OPT PSEUDOSECTION:
; EDNS: version: 0, flags:; udp: 65494
;; QUESTION SECTION:
;eu-west-2.compute.internal. IN A

;; Query time: 7 msec
;; SERVER: 127.0.0.53#53(127.0.0.53)
;; WHEN: Fri Apr 09 19:29:10 UTC 2021
;; MSG SIZE rcvd: 55

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Re: Site only accessible by IP, not domain name temporarily

by Najam Fazal - Friday, 9 April 2021, 2:52 PM

Right now at 11:36, the site is working flawlessly and mind you there are still 200 users. The CPU usage for past 3 hours

So, I am pretty confident that the VM can handle user requests and it is not the issue otherwise it would happen daily for the whole morning time from 8 am to 1 pm. Problem is there no downtime since Wednesday, however the usage pattern is the similar meaning students, teachers and admins are doing their usual things. So why CF is not making any issue right now? How come the same DNS route is working fine.

I will also put another site like wordpress or perhaps another moodle install in another directory and try to attach it to a separate subdomain with the same ISP and see if it causes the same issue at the same time when this moodle is inaccessible.

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Re: Site only accessible by IP, not domain name temporarily

by Visvanath Ratnaweera - Friday, 9 April 2021, 3:30 PM

I don't trust the silence. You used to have a vertical surge in load at 10 am. It is gone! Something has changed.

Further your htop 30 min earlier shows load average of 2.06/1.66/1.53. Why is it not reflected in the current graph?

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Re: Site only accessible by IP, not domain name temporarily

by Najam Fazal - Friday, 9 April 2021, 4:06 PM

That vertical surge was 1 hour aggregate (my bad that I wrote 5 min). This however is a 3-hour graph of 5 min aggregate. Though there are users who join in bulk like 100-200 users within minutes.

I don't know about the load average not reflecting. I mean it that's the case, both cores would show 100%, wouldn't it? So that may be something else.

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Re: Site only accessible by IP, not domain name temporarily

by Najam Fazal - Friday, 9 April 2021, 4:19 PM

Also, the issue really didn't occur since Wednesday, so I really can't say looking all this yield anything. It is actually the randomness that is really messing up the situation.

So if we segregate the things to look for:

CPU/Mem load: To be observed just before the down time because if its DNS then the request wouldn't even reach the machine. If CPU/Mem goes off the charts before the downtime, then load becomes a good candidate to account for.
Moodle (Code+DB): Anything here to be checked
DNS routing: To have a similar website (moodle) on the same machine connected to the another subdomain of the same main domain with the same domain registrar. This will ensure that routing is similar. If the dummy site is accessible from another subdomain (using the same primary DNS) at the same time while the main moodle site is down, then it's definitely the issue with the server (apache config).

Any other areas/test set up to make. Frankly, I think if a site is inaccessible for a time being by FQDN while, at the same time, accessible by IP, then it has nothing (or very less) with the application code or DB. But that's my intuition and small knowledge.

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Re: Site only accessible by IP, not domain name temporarily

by Visvanath Ratnaweera - Saturday, 10 April 2021, 2:28 PM

> It is actually the randomness that is really messing up the situation.

Random? I thought the down time coincides with the surges, typically at 10 am?

> CPU/Mem load: To be observed just before the down time because if its DNS then the request wouldn't even reach the machine. If CPU/Mem goes off the charts before the downtime, then load becomes a good candidate to account for.

CPU and memory utilization are just examples of any number of load parameters. There are more, I/O congestion (processes waiting for file read/write), DB queue, network traffic at the interface, ... If anything is excessive, at any time (independently of 10 am surge) you should investigate it.

> Moodle (Code+DB): Anything here to be checked

Could be part of the investigation above. You need clues. Otherwise, just to optimize the application you are going to need huge resources.

> DNS routing:

System software, web server, database server, OS, comes before the application. The network comes even before. So if you suspect something in the network, in the foundation, no point in looking at upper levels. So that is the place to start, and Ken has gone to lot of details. AFAIC, I am here because of Moodle and Linux. Debugging the network is out of bounds for me. Even if I am inclined, this cloud business Amazon, Azure, Cloudflare, .. are Spanisch to me.

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Re: Site only accessible by IP, not domain name temporarily

by Ken Task - Sunday, 11 April 2021, 12:32 AM

Prelim ... admin of a server does require some care and maintenance ... outside of Moodle ... period. No way round that. And that needs to be performed on regular basis!

OP granted me access to site via ssh for a 'free look-see' ...

First, nice that Ubuntu informs upon logging in ... 18.04 is soon to go EoL and notice by system says good idea to upgrade the OS soon. Same is true of MariaDB. PHP also has a minor update available.

OP tried to install mysqltuner via apt, but guess It's not available in repo, so installed in my user space and used MariaDB creds seen in config.php file of Moodle (don't think is superuser for DB server).

Aside from recommendations Tuner gave (below), a clip of what it reported:

[!!] failed to execute: SELECT CONCAT(user, '@', host) FROM mysql.user WHERE password = PASSWORD('baseball') OR password = PASSWORD(UPPER('baseball')) OR password = PASSWORD(CONCAT(UPPER(LEFT('baseball', 1)), SUBSTRING('baseball', 2, LENGTH('baseball'))))
[!!] FAIL Execute SQL / return code: 256

I've never/ever seen such as above! Anyone care to share what above is about?

MariaDB/MySQL has databases mysql.user, mysql.host which help setup users and host that can access the server - thus relate to security.

Best on a standalone server where everything that runs moodle lives on the same server to restrict host to only localhost and 1 or 2 users access from localhost. No outside/off server access to DB server and DB's therein allowed. More secure that way.

Tuner run and recommendations help explain observed behavior of site on testing days:

**** [!!] Highest connection usage: 100% (152/151)

**** [OK] Aborted connections: 0.02% (1345/8131144)

(isn't really ok ... 1345 isn't a good number ... on other servers I admin with same prox setup only 1 or 2 and those are usually me tweaking then restarting service ...)

**** [!!] InnoDB buffer pool / data size: 128.0M/9.3G

Default max connections is 151 ... that should be increased .. relates to concurrent connections by users ... ball park guess would be 451.

That change (as well as buffer pool settings) has to be made in my.cnf to make permanent. Pool currently set for default 128M needs to be at least 10G.

When one allocates more memory to DB server, one then needs to verify that overall memory still allows the OS to do it's thing and that apache service has enough to handle traffic.

So ... OP has some updates and config changes to make.

'SoS', Ken

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Re: Site only accessible by IP, not domain name temporarily

by Najam Fazal - Sunday, 11 April 2021, 3:21 PM

Sure. I will update and make changes as suggested. Emailed you further details.

That baseball database access is definitely strange. I will have a security look up of the server too.

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Re: Site only accessible by IP, not domain name temporarily

by Najam Fazal - Sunday, 11 April 2021, 3:20 PM

The randomness is not related to time but days. Besides having the same user loads last week, the server only became inaccessible (by FQDN only) on Tue and Wed around 10. Also, in weeks before, it happens on different days.

Regarding machines, I also discussed with Ken and I am going to make upgrades and config changes. I will observe the next week with this changes applied and see if I find something.

Thank you so much for all your advises.

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Re: Site only accessible by IP, not domain name temporarily

by Ken Task - Monday, 12 April 2021, 1:22 AM

Info not shared ... after a 'look-see', I see the site is like a K12 school in USA ... lower 'grades' up through 8th grade + other. And the site is using Zoom for F-2-F contact with students who are remote. Not a large user base ... about 3500 student + teacher accounts. Not that many courses either.

IF ... IF ... IF there are teachers who are requiring their students to be online and in Zoom at 10:00 am and those students are also taking a test which isn't configured to provide questions a chunk at a time, server could be struggling - well, really struggling.

DB (mariadb) is in need of tweaks to use more memory - mysqltuner recommendations ... there are php updates as well as other OS updates needed. Apache2buddy is making recommenations to tweak settings for apache as well. So now it's a balancing act ... DB config/Apache config and how some teachers might be conducting their class.

IF ... IF .... tweaks to MariaDB and Apache are too much for a standalone, then next step is to break off DB to another server dedicated to nothing but DB.

So this is a work in progress.

'SoS', Ken

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Re: Site only accessible by IP, not domain name temporarily

by Ken Task - Friday, 9 April 2021, 11:26 PM

dig learn.tld.org

learn.tld.org. 300 IN A 3.x.x.x

3.x.x.x is an amazon IP

dig learn.tld.org -t NS - query for name server auth for domain.

tld.org. 900 IN SOA ben.ns.cloudflare.com. dns.cloudflare.com. 2036749631 10000 2400 604800 3600

So from your workstation what DNS responses do you get for same queries?

In whatever interface you have to cloudflare, do you see any references to
learn.tld.org?

dig @ben.ns.cloudflare.com learn.tld.org

Does respond correctly with same 3.x.x.x IP

I see 2 DNS servers auth for tld.org

;; ANSWER SECTION:
tld.org. 86400 IN NS ben.ns.cloudflare.com.
tld.org. 86400 IN NS jasmine.ns.cloudflare.com.

ben.ns.cloudflare.com.    886    IN    A    108.162.193.103
ben.ns.cloudflare.com.    886    IN    A    173.245.59.103
ben.ns.cloudflare.com.    886    IN    A    172.64.33.103

'SoS', Ken

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Re: Site only accessible by IP, not domain name temporarily

by Najam Fazal - Saturday, 10 April 2021, 1:45 AM

Yes, its responding correct IP and both DNS on main domain.

From workstation:

# dig learn.tld.org -t NS

; <<>> DiG 9.16.1-Ubuntu <<>> learn.tld.org -t NS

;; global options: +cmd

;; Got answer:

;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 1233

;; flags: qr rd ra; QUERY: 1, ANSWER: 0, AUTHORITY: 0, ADDITIONAL: 1

;; OPT PSEUDOSECTION:

; EDNS: version: 0, flags:; udp: 65494

;; QUESTION SECTION:

;learn.tld.org. IN NS

;; Query time: 139 msec

;; SERVER: 127.0.0.53#53(127.0.0.53)

;; WHEN: Fri Apr 09 22:39:49 PKT 2021

;; MSG SIZE rcvd: 44

# dig tld.org -t NS

; <<>> DiG 9.16.1-Ubuntu <<>> tld.org -t NS

;; global options: +cmd

;; Got answer:

;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 63527

;; flags: qr rd ra; QUERY: 1, ANSWER: 2, AUTHORITY: 0, ADDITIONAL: 1

;; OPT PSEUDOSECTION:

; EDNS: version: 0, flags:; udp: 65494

;; QUESTION SECTION:

;tld.org. IN NS

;; ANSWER SECTION:

tld.org. 21599 IN NS ben.ns.cloudflare.com.

tld.org. 21599 IN NS jasmine.ns.cloudflare.com.

;; Query time: 131 msec

;; SERVER: 127.0.0.53#53(127.0.0.53)

;; WHEN: Fri Apr 09 22:40:14 PKT 2021

;; MSG SIZE rcvd: 95

# dig @ben.ns.cloudflare.com learn.tld.org

; <<>> DiG 9.16.1-Ubuntu <<>> @ben.ns.cloudflare.com learn.tld.org

; (6 servers found)

;; global options: +cmd

;; Got answer:

;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 35975

;; flags: qr aa rd; QUERY: 1, ANSWER: 1, AUTHORITY: 0, ADDITIONAL: 1

;; WARNING: recursion requested but not available

;; OPT PSEUDOSECTION:

; EDNS: version: 0, flags:; udp: 1232

;; QUESTION SECTION:

;learn.tld.org. IN A

;; ANSWER SECTION:

learn.tld.org. 300 IN A 3.8.241.83

;; Query time: 7 msec

;; SERVER: 172.64.33.103#53(172.64.33.103)

;; WHEN: Fri Apr 09 22:40:41 PKT 2021

;; MSG SIZE rcvd: 60

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Re: Site only accessible by IP, not domain name temporarily

by Ken Task - Saturday, 10 April 2021, 2:41 AM

Note; for others who might be lurking or find this thread later ...

tld.org isn't real!!! We are hiding the real top level domain of server.

Does Amazon have a status page for customers? A page that would show if DNS services at that .internal FQDN is up ... as well as secondaries to the primary?

From the server itself ... in an ssh session ... what does a traceroute or constant ping the .internal DNS server show?

Did you note? the top level domain (tld.org) points to clouldflare DNS's ... learn.tld.org does give Amazon IP but where is the response for the request of learn.tld.org really being generate?

From description sporadic access the only thing I can think that would cause that is loosing the first dns server that knows ... should then go to secondary dns server but hickup!!!! DNS servers should sync zones/records frequently. That's nothing you control.

In responses you'll see a number ... like: 300 or even larger like 21599 for the DNS servers. Also did you notice the query at ben. showed 6 ... 6 servers found ... all by different IP addresses ... kinda like fail safes that could be failing. :|

Like I said, however, don't host on Amazon. :|

Yes, PM me info/creds for accessing server. Not that I can fix or will fix .. curious mind. Might see something ... then again may not.

You, however, do install mysqltuner and apache2buddy.

Do you know the superuser creds to the DB server? (share via PM)

'SoS', Ken

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Re: Site only accessible by IP, not domain name temporarily

by Najam Fazal - Tuesday, 13 April 2021, 2:47 PM

The issue happened again on Monday but not today despite the similar load.

We are separating database on another machine to see if the load is the key issue. Had done some config changes after mysqltuner recommendations. Let's see if the issue arises tomorrow or this week.

Big thanks to Ken for his impeccable support!

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Re: Site only accessible by IP, not domain name temporarily

by Ken Task - Wednesday, 14 April 2021, 1:44 AM

Ok, am asking anyone ... anyone ... who host a moodle on Amazon.

Right now, OP's server is on a single Amazon web server ... Ubuntu 18.04 with MariaDB and Apache. Total memory is 8 Gig. MySQLTuner runs suggest, as it usually does, in creasing the innodb_buffer_pool_size and instances to cover the data InnoDB buffer pool / data size to at least 9Gig.

IF one does that, Maximum reached memory usage, Maximum possible memory usage, Overall possible memory usage with other process is compatible with memory available comes into play and a tuner run warn amount of memory for DB is pushing server into an un-stable state.

2 options ...

1. setup a dedicated DB server on Amazon where one can dedicate almost all of the memory to the DB.

2. increase the memory of existing server from 8 to 16. Amazon offers only increments in 8 Gig chunks ... nothing inbetween.

#1 involves networking ... DB server and Web server to be in same data center (London - customer [admin/teachers/students] are in South Asia)

OP has suspected a DNS issue and appears to be confusing DNS resolution for the Amazon server with routing. All of the users will be approximately 35 hops from servers in London. Nothing ... no change to any config of anything will reduce the number of hops.

IF ... IF ... you were admin/technical person of the moodle server such as described, would you do #1 or #2 above? No, entity is not interested in moving to another provider - so responses should not suggest moving off Amazon.

Above is technical, but am sure cost is also involved ... so any comment on that also welcomed!

Truth in questions ... I personally, do not host with Amazon and yes, have read as much as I can find ... but really can't find any such comparison that includes tech as well as cost and/or catch 22's!

Thanks, in advance,

'SoS', Ken

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Re: Site only accessible by IP, not domain name temporarily

by Najam Fazal - Friday, 16 April 2021, 5:59 AM

The server did not go down since Monday. The randomness is not off the checklist, so we wait and see.

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Re: Site only accessible by IP, not domain name temporarily

by Visvanath Ratnaweera - Friday, 16 April 2021, 3:16 PM

What are the changes you've done between then and now? Sorry, this is a long thread.

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Re: Site only accessible by IP, not domain name temporarily

by Najam Fazal - Saturday, 17 April 2021, 1:00 AM

We separate out the database on another machine with more RAM (16G). Changed a few settings recommended by MySQLTuner and Apache2Buddy, mainly max connections and buffer pool size and instances, so in a nutshell added more mem to the processes.

However, we have both web and db servers at the same location as before (London). This and next week will probably be a deciding factor if the web/db server was the issue or the network.

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Re: Site only accessible by IP, not domain name temporarily

by Ken Task - Saturday, 17 April 2021, 1:05 AM

Long thread due to me chasin' a mistaken rabbit hole! My fault there.

As far as resolution, kinda related to my last posting about options for hosting in Amazon, but, shall defer any response as to resolution (still in a 'wait and see' mode) to OP.

Will say internet really hasn't truely addressed the issues of 'last mile' (and devices used) as well as 'location, location, location'. No, won't explain that ... but those who have been involved with internet/moodle for some time now probably do understand what those 2 things mean!

Edit: see OP has responded ... thanks for that. So consider above to be a vague response. :|

'SoS', Ken

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Re: Site only accessible by IP, not domain name temporarily

by Visvanath Ratnaweera - Wednesday, 21 April 2021, 1:22 AM

Performance is at least a partial factor, since delegating the database to a new and powerful server and tuning it has vastly reduced the service outages. The open question is whether a long haul network is also partly responsible. That is indeed a tough (expensive) factor to eliminate for comparison. And, if proven, how to you change an intercontinental network route?

Now I see why you mentioned the location. I thought for an ice parlor yes, but for a server? What can you do other than docking it tightly to an Internet highway? In any case, these reports convinced me that I have no clue how the "cloud" works: https://www.washingtonpost.com/technology/2020/11/28/amazon-outage-explained/.

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Re: Site only accessible by IP, not domain name temporarily

by Ken Task - Wednesday, 21 April 2021, 2:15 AM

As in internet of old (still true) ... 'last mile' and, just like brick and mortar business ... 'location, location, location'.

'SoS', Ken

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Re: Site only accessible by IP, not domain name temporarily

by Najam Fazal - Wednesday, 21 April 2021, 1:56 PM

No issues this week so far. Will observe for two more days and call this one off as a server capacity issue.

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