Users of my sites expierence random timeouts

[cisman]

I have a dedicated server with Fedora and Cpanel on it. I've noticed that when browsing my hosted sites at time it will timeout and won't be able to resolve my site for about 30 seconds to a minute. It happens randomly and it happens at all times.

So it's not something that happens when the server load is high...which my server load stays pretty low.

It's happened when my server load is at .77. My server is a Dual Xeon 2.8 Ghz machine with 2GB RAM.

Any ideas on what's causing this?

Is it a BIND issue?

Apache issue? (I've changed apache settings to the optimized options you find on the web with no result)

I'm at a loss.

 

[chirpy]

It's more than likely a DNS issue. If that's the case, then using www.dnsreport.com with your domain name should highlight any issues. If it were an apache issue you would expect errors in /usr/local/apache/logs/error_log when it happens. It can also be caused by a faulty router table at your NOC, but I'd look into the first two before going down that route.

 

[cisman]

The only error I had at that site was this.

ERROR: One or more of your nameservers reports that it is an open DNS server. This usually means that anyone in the world can query it for domains it is not authoritative for (it is possible that the DNS server advertises that it does recursive lookups when it does not, but that shouldn't happen). This can cause an excessive load on your DNS server. Also, it is strongly discouraged to have a DNS server be both authoritative for your domain and be recursive (even if it is not open), due to the potential for cache poisoning (with no recursion, there is no cache, and it is impossible to poison it). Also, the bad guys could use your DNS server as part of an attack, by forging their IP address. Problem record(s) are:

Ok...fixed that with the suggestions give by dnsreport.

 

[chirpy]

That should rule out a DNS problem then as that error isn't relevant to the problem. Did the nameserver at dnsreport tally with what you expected them to be? If so, then you need to double check the apache logs and ultimately ask your NOC if it's possible the router cache is having problems to your server and explain the symptoms to them.

 

[webignition]

I have a dedicated server with Fedora and Cpanel on it. I've noticed that when browsing my hosted sites at time it will timeout and won't be able to resolve my site for about 30 seconds to a minute. It happens randomly and it happens at all times.

I've been experiencing the exact same issues for as long as I can recall (about a year and a half).

I have only recently figured out that this is due to my DSL provider refreshing my (dynamically assigned) IP address.

 

[cisman]

The only other warning I got was this from the DNS report.

WARNING: Your SOA REFRESH interval is : 86400 seconds. This seems high. You should consider decreasing this value to about 3600-7200 seconds (or higher, if using DNS NOTIFY). RFC1912 2.2 recommends a value between 1200 to 43200 seconds (20 minutes to 12 hours, with the longer time periods used for very slow Internet connections), and if you are using DNS NOTIFY the refresh value is not as important (RIPE recommend 86400 seconds if using DNS NOTIFY). This value determines how often secondary/slave nameservers check with the master for updates. A value that is too high will cause DNS changes to be in limbo for a long time.

WARNING: Your SOA EXPIRE time is : 3600000 seconds. This seems a bit high. You should consider decreasing this value to about 1209600 to 2419200 seconds (2 to 4 weeks). RFC1912 suggests 2-4 weeks. This is how long a secondary/slave nameserver will wait before considering its DNS data stale if it can't reach the primary nameserver.

webignition: Would it affect all my other users and if it's my connection I would be able to browse any other site. It seems to only affect my site.

I'll check the apache error logs.


Wait it's pretty full over 18000 lines.

Tons of these with your usual file does not exist error.

[Thu Jun 29 18:35:56 2006] [notice] child pid 20171 exit signal File size limit exceeded (25)
[Thu Jun 29 18:35:56 2006] [notice] child pid 20174 exit signal File size limit exceeded (25)
[Thu Jun 29 18:35:56 2006] [notice] child pid 20175 exit signal File size limit exceeded (25)
[Thu Jun 29 18:35:56 2006] [notice] child pid 20176 exit signal File size limit exceeded (25)
[Thu Jun 29 18:35:56 2006] [notice] child pid 20177 exit signal File size limit exceeded (25)
[Thu Jun 29 18:35:56 2006] [notice] child pid 20178 exit signal File size limit exceeded (25)
[Thu Jun 29 18:35:56 2006] [notice] child pid 20182 exit signal File size limit exceeded (25)
[Thu Jun 29 18:35:56 2006] [notice] child pid 20183 exit signal File size limit exceeded (25)
[Thu Jun 29 18:35:57 2006] [notice] child pid 20068 exit signal File size limit exceeded (25)
[Thu Jun 29 18:35:57 2006] [notice] child pid 20173 exit signal File size limit exceeded (25)
[Thu Jun 29 18:35:57 2006] [notice] child pid 20180 exit signal File size limit exceeded (25)
[Thu Jun 29 18:35:57 2006] [notice] child pid 20181 exit signal File size limit exceeded (25)
[Thu Jun 29 18:35:57 2006] [notice] child pid 20186 exit signal File size limit exceeded (25)
[Thu Jun 29 18:35:57 2006] [notice] child pid 20187 exit signal File size limit exceeded (25)
[Thu Jun 29 18:35:57 2006] [notice] child pid 20215 exit signal File size limit exceeded (25)
[Thu Jun 29 18:35:57 2006] [notice] child pid 20216 exit signal File size limit exceeded (25)
[Thu Jun 29 18:35:57 2006] [notice] child pid 20219 exit signal File size limit exceeded (25)
[Thu Jun 29 18:35:57 2006] [notice] child pid 20220 exit signal File size limit exceeded (25)
[Thu Jun 29 18:35:57 2006] [notice] child pid 20223 exit signal File size limit exceeded (25)
[Thu Jun 29 18:35:57 2006] [notice] child pid 20227 exit signal File size limit exceeded (25)
[Thu Jun 29 18:35:58 2006] [notice] child pid 20103 exit signal File size limit exceeded (25)
[Thu Jun 29 18:35:58 2006] [notice] child pid 20179 exit signal File size limit exceeded (25)
[Thu Jun 29 18:35:58 2006] [notice] child pid 20184 exit signal File size limit exceeded (25)
[Thu Jun 29 18:35:58 2006] [notice] child pid 20218 exit signal File size limit exceeded (25)
[Thu Jun 29 18:35:58 2006] [notice] child pid 20222 exit signal File size limit exceeded (25)
[Thu Jun 29 18:35:58 2006] [notice] child pid 20224 exit signal File size limit exceeded (25)
[Thu Jun 29 18:35:58 2006] [notice] child pid 20228 exit signal File size limit exceeded (25)
[Thu Jun 29 18:35:58 2006] [notice] child pid 20229 exit signal File size limit exceeded (25)
[Thu Jun 29 18:40:33 2006] [error] mod_gzip: TRANSMIT_ERROR:ISMEM:104

 

[webignition]

Would it affect all my other users and if it's my connection I would be able to browse any other site. It seems to only affect my site.

You would think that it wouldn't affect all other users and that it would affect your connectivity as a whole, as would I.

It's probably then not related as I haven't heard of any of my users having similar problems and it wasn't clear from your first post that this was affecting more than just yourself.

 

[bofla]

[Thu Jun 29 18:35:56 2006] [notice] child pid 20171 exit signal File size limit exceeded (25)

means that domlogs/ has a file larger than 2GB. Stop apache, go to /usr/local/apache/domlogs and echo "" > domain.com, start apache. That will clear the log file (stats will not be available for that period).

To find a file larger than X, try executing this in domlogs/
find . -size +1000000k -exec ls -l {} \; -print

 

[rpmws]

This may or not be an issue but I have seen more than my fair share of it. I tell people to use http://pingplotter.com and run it on 1second intervals against your IP address on your server. This program is great. It pings and graphs every network hop over and over to find when and how often there is latency or time-outs. Not only does it do that but you can have it run for days and you can then activate the graph for EACH network hop all the way to your site. You can scroll through the charts and click on the red areas and see exactally what point the network connection between you and your server failed and how long it lasted and where in the network it started. I run it all the time. It will rule out packet loss at your data center and everywhere in between. Don't go spending time trouble shooting the server if it's just packetloss. Make sure that's not it first.