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CENTOS 5 Ping Problem

Hi.
Can anybody explain why this is happening?

Code:

64 bytes from py-in-f99.google.com (64.233.167.99): icmp_seq=1 ttl=243 time=150 ms

64 bytes from py-in-f99.google.com (64.233.167.99): icmp_seq=2 ttl=243 time=151 ms

64 bytes from py-in-f99.google.com (64.233.167.99): icmp_seq=3 ttl=243 time=151 ms

64 bytes from py-in-f99.google.com (64.233.167.99): icmp_seq=4 ttl=243 time=153 ms

ping: sendmsg: Operation not permitted

ping: sendmsg: Operation not permitted

64 bytes from py-in-f99.google.com (64.233.167.99): icmp_seq=7 ttl=243 time=153 ms

64 bytes from py-in-f99.google.com (64.233.167.99): icmp_seq=8 ttl=243 time=149 ms

ping: sendmsg: Operation not permitted

ping: sendmsg: Operation not permitted

64 bytes from py-in-f99.google.com (64.233.167.99): icmp_seq=11 ttl=243 time=152 ms

64 bytes from py-in-f99.google.com (64.233.167.99): icmp_seq=12 ttl=243 time=151 ms

ping: sendmsg: Operation not permitted

ping: sendmsg: Operation not permitted

ping: sendmsg: Operation not permitted

64 bytes from py-in-f99.google.com (64.233.167.99): icmp_seq=16 ttl=243 time=152 ms

ping: sendmsg: Operation not permitted

64 bytes from py-in-f99.google.com (64.233.167.99): icmp_seq=18 ttl=243 time=151 ms

ping: sendmsg: Operation not permitted

ping: sendmsg: Operation not permitted

This happens for any site, not just google.

The server runs mysql, php & apache and is quite busy.

I think this may be causing connection errors for users also (including myself) so am quite keen to get this sorted, although the load is under 1 so I am suprised by the un-responsiveness of the pages served, and the pings going out!

Thanks.

edit: Ok so I stopped the httpd service and it pings ok now.
So this error must occour becuase Apache is overloading the server?

Can anybody give me any advice as how to stop this happening? Maybe increase the amount of active connections?
Ta.

Are there any errors in Apache's error log?

That is typically a networking problem, that is when the kernel refuses to transmit the packet, am suspecting congestion on the wire.

Quote:

Originally Posted by falko

Are there any errors in Apache's error log?

None, well apart from some 'file does not exist' errors caused by people not updating their bookmarks.

Quote:

Originally Posted by topdog

That is typically a networking problem, that is when the kernel refuses to transmit the packet, am suspecting congestion on the wire.

Sounds fair, if this is the case what would my options be?
And how can I test this is the case?

edit: Do you mean my hosts bandwidth? Or my server?

Thanks again for the help guys.

Thanks, I use APF. I will read through the links and post back :)

One of the links referring to memchached I dont use (one of these days Il get my head round it and use it tho!) eaccelarator does me for now.

Looking at this link:
http://www.netfilter.org/documentati...q-3.html#ss3.7

It says to increase the number of connectinos.... but my ip_conntrack_max is already set to 34576.
Is it ok to up this?

Cheers again ;)

Have you tried to disable APF to find out if it really is the firewall that's causing the problem?

Tried disabling APF with no success, still the same issue.
Stopped mysqld service (didnt think would make a difference but thought I better try) and again, no difference.

Stopped httpd service, and voila, no more ping problems. So it def seems like its the number of connections coming from Apache that are causing the issue.

Im going to look into apache optimization for now but if you have any quick tips I would apreciate it!

Also see my top output

Code:

top - 14:06:23 up 38 days, 13:18,  1 user,  load average: 1.48, 1.89, 1.46

Tasks: 154 total,   1 running, 153 sleeping,   0 stopped,   0 zombie

Cpu(s): 31.9%us, 10.3%sy,  0.0%ni, 49.5%id,  3.0%wa,  0.0%hi,  5.3%si,  0.0%st

Mem:   1994020k total,  1562692k used,   431328k free,   110104k buffers

Swap:  2031608k total,       96k used,  2031512k free,  1040928k cached



  PID USER      PR  NI  VIRT  RES  SHR S %CPU %MEM    TIME+  COMMAND

10388 mysql     15   0  563m  91m 4076 S 12.3  4.7   0:58.58 mysqld

10419 root      25   0  291m 9728 5288 S  1.0  0.5   0:00.58 httpd

11534 apache    15   0  292m 8756 3180 S  1.0  0.4   0:00.04 httpd

11543 apache    15   0  292m 8692 3180 S  1.0  0.4   0:00.04 httpd

11118 apache    15   0  294m  12m 5808 S  0.7  0.7   0:00.51 httpd

11126 apache    16   0  294m  13m 6332 S  0.7  0.7   0:00.56 httpd

11129 apache    15   0  292m 9024 3400 S  0.7  0.5   0:00.45 httpd

11172 apache    15   0  293m  11m 5416 S  0.7  0.6   0:00.24 httpd

11176 apache    15   0  293m 9140 3396 D  0.7  0.5   0:00.23 httpd

11185 apache    15   0  292m 9212 3528 S  0.7  0.5   0:00.25 httpd

11193 apache    15   0  294m  13m 6380 S  0.7  0.7   0:00.29 httpd

11197 apache    15   0  294m  12m 5716 S  0.7  0.7   0:00.29 httpd

11198 apache    15   0  294m  13m 6332 S  0.7  0.7   0:00.30 httpd

11217 apache    15   0  292m 8908 3260 S  0.7  0.4   0:00.24 httpd

11221 apache    15   0  292m 8904 3312 S  0.7  0.4   0:00.24 httpd

11527 apache    15   0  292m 8764 3180 S  0.7  0.4   0:00.06 httpd

11530 apache    15   0  292m 8736 3180 S  0.7  0.4   0:00.04 httpd

11533 apache    15   0  292m 8720 3172 S  0.7  0.4   0:00.05 httpd

11536 apache    15   0  292m 8712 3164 S  0.7  0.4   0:00.05 httpd

11538 apache    15   0  292m 8784 3164 S  0.7  0.4   0:00.03 httpd

11541 apache    15   0  292m 8720 3164 S  0.7  0.4   0:00.05 httpd

11544 apache    15   0  292m 8740 3188 S  0.7  0.4   0:00.02 httpd

11547 apache    16   0  292m 8708 3164 D  0.7  0.4   0:00.02 httpd

11548 apache    15   0  292m 8700 3164 S  0.7  0.4   0:00.02 httpd

11553 apache    15   0  292m 8664 3164 S  0.7  0.4   0:00.02 httpd

11092 root      15   0 12716 1104  788 R  0.3  0.1   0:00.54 top

11158 apache    15   0  294m  13m 6380 S  0.3  0.7   0:00.50 httpd

11186 apache    15   0  292m 8896 3232 S  0.3  0.4   0:00.25 httpd

11187 apache    15   0  292m 9488 3700 S  0.3  0.5   0:00.26 httpd

11205 apache    15   0  292m 8896 3220 S  0.3  0.4   0:00.23 httpd

11229 apache    15   0  294m  13m 5896 S  0.3  0.7   0:00.28 httpd

11528 apache    16   0  292m 8784 3196 S  0.3  0.4   0:00.03 httpd

11531 apache    15   0  292m 8712 3212 S  0.3  0.4   0:00.02 httpd

11535 apache    15   0  292m 8740 3176 S  0.3  0.4   0:00.04 httpd

11537 apache    15   0  294m  12m 5260 S  0.3  0.6   0:00.06 httpd

11540 apache    15   0  292m 8732 3180 S  0.3  0.4   0:00.03 httpd

The number of httpd connections can vary dramatically from 1 to all that you can see above, which shoots up the amount of processor being used.
Should this be happening?

Ok so I used this guide:
http://www.howtoforge.com/configurin...um_performance

And it seems to have helped server speed but I am still getting the 'operation not permitted' errors when pinging out.

I changed the following

Code:

KeepAlive Off

KeepAliveTimeout 15

<IfModule prefork.c>

StartServers       8

MinSpareServers    5

MaxSpareServers   20

ServerLimit      256

MaxClients       256

MaxRequestsPerChild  4000

</IfModule>

Code:

KeepAlive On

KeepAliveTimeout 5

<IfModule prefork.c>

StartServers       20

MinSpareServers    30

MaxSpareServers   50

ServerLimit      256

MaxClients       256

MaxRequestsPerChild  3000

</IfModule>

Do you think I should increase the ServerLimit & MaxClients variables too?

Next step I guess is to work out what modules I need to keep enabled (all default modules are still being loaded). More reading for me I guess!