[Linux-cluster] apache resource problem in RHCS 5.1

Lorenz Pfiffner lp at xbe.ch
Tue Jun 17 07:19:33 UTC 2008


I want to add something I recently found out about the relocation time of IP resources, which I complained about.

The reason why it takes 10 seconds per IP can be found here: http://sources.redhat.com/cluster/faq.html#rgm_failovertime

Greetz
Lorenz

Marek 'marx' Grac wrote:
> Hi,
> 
> Lorenz Pfiffner wrote:
>> Hi Ron
>>
>> I couldn't make it working with the apache resource. For me it seems 
>> quite unstable and it's nowhere really mentioned in any documentation 
>> I found. So please, if any RedHat guy is reading this, can you please 
>> improve this feature and put it into the official documentation. For 
>> example, why does the apache.sh script change the "Listen" directive?
> Look at my previous post to this thread. IMHO unstable is something that 
> does not work.
> 
>> How can I execute apache.sh manually to debug the resource?
>>
> If you want to debug, the best way is to run resource group manager in 
> debug mode. So stop it in all machines, and run clurgmgrd -fd  (stay 
> forward and debug). Resource agents tries to log as much as is useful 
> and you will see everything on output. If you want to run this script 
> directly, you will have to setup all environment variables OCF_*.
> 
>> My workaround: I altered the default httpd script and made a script 
>> resource. In that case it's working as expected. The only thing that 
>> bothers me quite a lot is the relocation time. It takes about 50 to 60 
>> seconds to relocate 5 IPs, a GFS mount and the apache script resource! 
>> Is this a reasonable time? On older clusters I remember times around 5 
>> to 10 seconds.
> 
> Default init script for httpd, mysqld, ... will work for you if you have 
> only one httpd on your cluster. It is not suitable for running several 
> instances on same machine. This is one of the reasons why we need 
> resource agents.
> 
> 




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