I have a web server running on a EC2 c1.medium intance.

The instance is running on ubuntu, with apache2 and mysql.The ubuntu and apache version are the next;

Ubuntu
DISTRIB_ID=Ubuntu
DISTRIB_RELEASE=11.04
DISTRIB_CODENAME=natty
DISTRIB_DESCRIPTION="Ubuntu 11.04"

Apache2
Server version: Apache/2.2.17 (Ubuntu)
Server built:   Feb 22 2011 18:33:02

• Sometimes randomly, my server "hangs up", I cannot connect to it using normal web access or ssh access.

• If I reboot the instance it reboots fine, the amazon system log doesn't show anything weird, but the problem persists

• The only way to solve it its stopping the instance, and start it again.

I think that the problem its has something to do with apache, because the last lines of the error log lists:

normal errors
[Sun Jun 19 06:25:09 2011] [notice] Apache/2.2.17 (Ubuntu) PHP/5.3.5-1ubuntu7.2 with Suhosin-Patch configured -- resuming normal operations
nobody cant connetc... no more erros until i stop and start the instance

normal errors
[Wed Jun 22 14:21:18 2011] [notice] Apache/2.2.17 (Ubuntu) PHP/5.3.5-1ubuntu7.2 with Suhosin-Patch configured -- resuming normal operations
nobody cant connetc... no more erros until i stop and start the instance

Can somebody please help me?