[CentOS] Apache Issue on CentOS 6

Mon Apr 8 04:54:37 UTC 2013
Banyan He <banyan at rootong.com>

I did a quick test on el5 and el6 with these package,


I kept the configuration as what it is in default. The index page is 
about 7k, 100 connections per second. I barely find the connection is 
marked as R. Mostly C and _. This is done by ab from httpd.

I also did a quick test with slow attack. It's basically slowing the 
client itself to collect the data from the server. I did 200 connections 
per second. My server is ok seems. A little bit slow, but not too much.





I also did the capture on the network traffic that I can find out the 
connections are doing something bad. You may follow the lead here as I 

Banyan He
Blog: http://www.rootong.com
Email: banyan at rootong.com

On 4/7/2013 12:23 AM, linuxsupport wrote:
> There is no problem with the hardware, If I installed CentOS 5 then it 
> works well, at a time out of total 44 concurrent requests 34 were in 
> reading state
> On Sat, Apr 6, 2013 at 2:03 PM, Banyan He <banyan at rootong.com 
> <mailto:banyan at rootong.com>> wrote:
>     I went to the source code to check this. Seems like it's used for
>     against the slow request attack from the rate. There is a timeout
>     and rate set for header and body.
>     I'd keep that thought, capture one connection from tcpdump seeing
>     if they are doing something bad. If not, you seem need a new
>     server balancing the traffic.
>     ------------
>     Banyan He
>     Blog:http://www.rootong.com
>     Email:banyan at rootong.com  <mailto:banyan at rootong.com>
>     On 4/6/2013 3:06 PM, linuxsupport wrote:
>>     I have already checked but all requests are from different IP's
>>     and even different subnet
>>     When there are less requests it works ok even if there are more
>>     than 60% reading requests but during peak time when concurrent
>>     requests goes beyond 150, due to reading requests it becomes 300+
>>     requests processing at the same time and that then Apache stop
>>     responding as maxclient is set to 300. CPU load also goes up and
>>     thing become very slow.
>>     On Sat, Apr 6, 2013 at 10:33 AM, Banyan He <banyan at rootong.com
>>     <mailto:banyan at rootong.com>> wrote:
>>         I'd recommend you to sort out the connections. Find out if
>>         they are coming from the same client or the same subnet of
>>         the clients. Doing a simple tcpdump capture to analyze the
>>         data seeing if it's a good R or a bad R.
>>         Don't really think it's because of the version.
>>         ------------
>>         Banyan He
>>         Blog: http://www.rootong.com
>>         Email: banyan at rootong.com <mailto:banyan at rootong.com>
>>         On 4/6/2013 12:24 PM, linuxsupport wrote:
>>             I am facing a problem with Apache on CentOS 6
>>             Apache 2.2.19 is complied from source.
>>             I see so many reading requests in Apache status page, as
>>             per my previous
>>             experience this "reading request" issue mainly comes when
>>             any of the
>>             internet route having any problem and it request takes
>>             time to completely
>>             reach to Apache, but this time there is no network issue.
>>             I have ran same setup on CentOS 5 it works well, but on
>>             CentOS 6 it show
>>             60%+ reading requests, web site has 20-25 requests per
>>             second that becomes
>>             80+
>>             I also tried to upgrade Apache to 2.2.24 but it is same
>>             on new version as
>>             well.
>>             Anyone else has experienced this issue?
>>             _______________________________________________
>>             CentOS mailing list
>>             CentOS at centos.org <mailto:CentOS at centos.org>
>>             http://lists.centos.org/mailman/listinfo/centos