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Occasional Transient APR::Table Error

Occasional Transient APR::Table Error

by Geoff Goehle -
Number of replies: 6
Every once in a while I will try to do something (log in, visit a homework page, submit a problem, it varies) and I will get the following error: 

Failed to initialize course environment: Could not evaluate global environment file /opt/webwork/webwork2/conf/global.conf: Can't locate object method "get" via package "APR::Table" at /opt/webwork/webwork2/lib/Apache/WeBWorK.pm line 74.

If I go back and submit again the error goes away and everything works as normal. Any suggestions? 
In reply to Geoff Goehle

Re: Occasional Transient APR::Table Error

by Geoff Goehle -
Looks like this has been seen by other people: 


The server I am on is using Red Hat, which seems to be one of the distros affected by this.  If that thread had a solution, I didn't see it.  
In reply to Geoff Goehle

Re: Occasional Transient APR::Table Error

by Gavin LaRose -
Hi Geoff,

We just upgraded our production server and moved it to RHEL 6 and haven't seen the error since. That said, we're not in the regular semester when loads are much higher and it would be more likely that we would see the error. Further, the new server is unloading requests faster than the old one, which I think reduces the chance of seeing the error.

For what it's worth,
Gavin
In reply to Gavin LaRose

Re: Occasional Transient APR::Table Error

by Richard Bayne -
Hello Gavin,
I am not clear here. Is there a solution to this problem? We are using Ubuntu, probably 8.04 and several students get this error when trying to submit answers. I tried to follow the discussion on the link in the message above, but I was not able to interpret. Is there no solution other than a reinstallation?
Richard Bayne
In reply to Richard Bayne

Re: Occasional Transient APR::Table Error

by Geoff Goehle -
This is a super late response.  

We upgraded to the latest apache release on our Red Hat server and the error is much less frequent.  I've only had one report of it in the last two weeks and haven't seen it at all myself. 

I don't know if this qualifies as "fixed" or not.  :P
In reply to Geoff Goehle

Re: Occasional Transient APR::Table Error

by Gavin LaRose -
Hi Richard & Geoff,

We haven't seen the error since upgrading our server and moving to RHEL (Red Hat Enterprise Linux) 6. We're now two weeks into the fall semester and some 2 million hits on the WeBWorK install, so I'm willing to say that we're no longer experiencing this problem.

We never found a work-around or solution when we were using the previous version of RHEL for our server. My guess was that the problem had to do with thread management or initialization in the apache server, and that the improved speed of our current server or the software upgrade (we moved from Red Hat's patched apache 2.2.3 to 2.2.15) has fixed the error.

I would assume that the errors on other Linux distributions (e.g., Ubuntu) would be caused by the same thing that caused them on Red Hat, and that either a software or hardware upgrade would resolve them. But in that I don't know for certain what the bug was that caused the error, I can't say for certain.

For what it's worth,
Gavin
In reply to Richard Bayne

Re: Occasional Transient APR::Table Error

by Richard Bayne -
Hello Gavin,
As often happens with me, the easy fix was not a fix. After making the change to WeBWorK.pm, there was no apparent change in results and I got the same warning message as before. It looks like I shall be installing a more modern version and see if that solves the problem.
Thanks, Richard