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i have an apache 2.2 with

ServerLimit        50
MaxClients         50

now when i run jmeter wth 50 threads and keep alive checked, all slots belong to jmeter. And i can't access the page with my browser.

i aleady tried

MaxRequestsPerChild  1

but this didn't change any thing

is there any out-of-the-box solution in apache to prevent one client using all slots?

share|improve this question
What actual problem are you trying to solve? This is essentially how Prefork works. Depending on the problem, there are different possibly solutions. – Chris S Sep 6 '13 at 13:19
the problem is that someone can dos my server just by running jmeter with 50 threads. And no other client will getting any response – wutzebaer Sep 6 '13 at 13:31
Have you tried using mod-evasive? It's specifically designed to detect DoS attacks and block their IP at the firewall level. – Chris S Sep 6 '13 at 13:55
up vote 0 down vote accepted

I don't see this specified, so try adding KeepAliveTimeout 5 to your apache configuration. Also, why only 50 MaxClients? You must have a very tiny server for it to be set this low.

MaxRequestsPerChild doesn't do anything as any requests through a KeepAlive counts as a single request as far as Apache is concerned. In this configuration (prefork), you can leave out ServerLimit entirely.

share|improve this answer
if i set it to 150 i can set jmeter to 150 threads... thats no solution.. and KeepAliveTimeout won't work because jmeter runns infinite and does not time out – wutzebaer Sep 6 '13 at 20:16
Why are you using jmeter to do this? Apachebench (ab) is a much better indication of real-world usage. However, you can take a look at mod_evasive and configure it to prevent client exhaustion. – Nathan C Sep 7 '13 at 1:07

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