we apply online testing to our students by testing 26 students at one time, it was working fine, but recently they can not log in at the same time, all browsers chrome, firefox, and IE keep saying "'name of browser' cannot connect to 'our moodle's link' " the only solution is to make them log in to their accounts and to exam some by some and the same for submitting their answers and logging out.
why this happening? and how we can solve it?
However, it's hard to help as you have not told us anything about your system. What version of Moodle, what server software, what hardware spec etc etc??
A list of the typical system information the helpers need is listed in the introduction to this (Hardware and Performance). I quote:
"Please include as much background information as possible about your hardware, the operating system, the web server, the database server, the PHP scripting framework, etc. If your machine is virtualized, also mention the host hardware, the operating system, the virtualization technology used and the resources assigned to the guest OS."