[Wylug-discuss] Linux server assistance

[David Watson]

On 05/11/12 20:14, Lee Evans wrote:
>
> Hi all,
>
> We have a client with a linux web server (apache, mysql, php) running 
> some wordpress sites.
>
> They are a relatively high volume site.
>
> We have been having some trouble with outages, which I suspect to be 
> due to load (and possibly malicious at that) issues.
>
> The server locks up or grinds to a halt, there are far more httpd 
> processes running than normal yet the usage stats suggest that there 
> aren't many live users.
>
> My personal suspicion given the symptoms is a targeted DDoS attack 
> using some sort of SYN flood to open too many connections which have a 
> dead end.
>
> Is there anyone out there that would be interested in helping us get 
> to the bottom of this?
>
> It's beyond our skill set with general server / apache installation 
> and maintenance.
>
>

This sounds like very similar symptoms to the ones we suffered during 
early deployment of wordpress, which was down to insufficient memory.

Check current usage (free or top) and look at the memory used per httpd 
process and the max processes in your apache.conf

Dave
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