[LON-CAPA-users] Unresponsive lon-capa

D G Teed lon-capa-users@mail.lon-capa.org
Mon, 7 Feb 2011 13:01:45 -0400

On Mon, Feb 7, 2011 at 12:00 PM, Stuart Raeburn <raeburn@msu.edu> wrote:
> Hi,
> Gerd mentioned the Apache server-status page: "http://(yourserver)/server-status/" and indicated he would send the password to access this page.
> Starting with LON-CAPA 2.8.0 access to this page (and some other status pages) was switched from using htpasswd-based authentication and authorization, to using access control via LON-CAPA (and configured for a domain by the Domain Coordinator).
> When logged into LON-CAPA, Domain Coordinators can view this page via:
> Main Menu -> Status of domain servers -> Apache Server Status
> A Domain Coordinator can also configure access to this page via:
> Main Menu -> Set domain configuration -> Display [Access to server status pages (checked)]
> One of the access modes supported is IP-based, which permits display of server-status from a specified machine without the need for log-in to LON-CAPA.  This can be useful for remote monitoring.
>> Yes, http://(yourserver)/server-status/
>> - that will show you what the server is busy doing and you can find  the problem that's the problem. I'll send you passwords in a minute.
> There can be a difficulty here in that once Apache has reached its maximum clients limit, and all clients are busy, possibly serving looped processes, it is difficult to get a free Apache client to display the server-status page.

A non-responding apache service has been the consistent
problem.  Last year I saw cases where the I/O was
grinding the server to death and it wasn't responsive
in any way.  But in the last case, it only impacted the
apache service, and the page would not display for
login - nothing at all, but browser timeouts trying
to reach it.  Even the logs were silent when I tried to
get the login screen.

So what's plan B?  There must be another way to get the
information on the back end if I have a healthy ssh login.

Also, when attempting access to Set Domain Configuration,
while at this time the apache service is responding
normally, I saw an error just now:

Something somewhere went wrong... etc. - the report form.

The error was:

Internal info:

Undefined subroutine &Apache::domainprefs::handler called.


In the error.log:

Undefined subroutine &Apache::domainprefs::handler called.\n

I guess I'm missing some perl modules or mine are out of date.

I'm able to get to the server-status page at this moment using the
"Status of domain servers" link.  I'll try monitoring this in case it
is useful.

--Donald Teed