Network scalability for 600 concurrent users

Network scalability for 600 concurrent users

by Kompli Tivi -
Number of replies: 4
I would like to improve my network bottleneck. When the users are busy, it seems like the CPU / memory not fully utilized, some users experienced network drops.

Current specs :
3rd gen xeon 6 cores / 12 threads.
32gb ram
SSD in raid 1
1 gigabit Intel nic using 1 public IP.
speedtest at 300 mbps down and 500 up.

Ubuntu with apache and php-fpm, 50GB mariadb optimized  with MySQLTuner with 24gb allocated to the memory.
The server is on cloudflare caching.

Total users around 6000, on a normal day 200-300 concurrent.
I'm expecting around 600-800 concurrent (it's mid term).
From my experience, users start complaining after 400, not all just a few.
My CPU never ran over 30% and memory is peaked at 16-18gb.
With those stats, i suspect a network bottleneck.

Question:
- how many users theoretically can connect to my server? Is there a hardware limitation using only 1 nic?
- will adding multiple nic / IP solve my problem?
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In reply to Kompli Tivi

Re: Network scalability for 600 concurrent users

by Visvanath Ratnaweera -
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In case my earlier comment doesn't make sense, it was a random guess based on many cases where the "bottleneck" was an upper limit in the system software, which was still at its default value. MaxRequestWorkers was an example, which may or may not apply.

Coming back to your question, you say the network is the bottleneck. Where is the evidence?

Did you investigate why the 1 Gbit/s interface delivers only 300 Mbit/s down and 500 Mbit/s up?

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In reply to Kompli Tivi

Re: Network scalability for 600 concurrent users

by Howard Miller -
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Most decent network switches will graph the traffic going through them - so that's the obvious route to checking that. I doubt it, however. The only time I had a problem with network capacity was between Moodle and our Redis server. But it still pays to check.

Similarly, you should be running some sort of monitoring software and checking *everything* you can check.
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In reply to Kompli Tivi

Re: Network scalability for 600 concurrent users

by Le Minh Tuan -
- I think you should not put all in one on same server.
- do you check max request config apache?
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