This happends not every day, but from time to time. SIM (system intergrity monitor) reports that "http url request failed" and keeps restarting Apache every 5 minbutes. At the same time SIM log shows that HTTP is online.

What can cause this problem of "url request failed" and what can I do to resolve it?

Thanks.



- SIM Log:
[04/07/09 14:10:01]: HTTP service is online.
[04/07/09 14:10:01]: HTTP url request failed, assuming offline.
[04/07/09 14:10:01]: Restarted HTTP service (11 HTTP events today).
[04/07/09 14:10:01]: Restarted HTTP service (11 HTTP events today).
[04/07/09 14:10:01]: MYSQL service is online.
[04/07/09 14:15:01]: could not lock subsys, aborting.
[04/07/09 14:15:01]: LOAD 0.11 (status good)
[04/07/09 14:15:01]: NETWORK is online.
[04/07/09 14:15:01]: HTTP service is online.
[04/07/09 14:15:01]: HTTP url request failed, assuming offline.
[04/07/09 14:15:01]: HTTP service is online.
[04/07/09 14:15:01]: HTTP url request failed, assuming offline.
[04/07/09 14:15:01]: HTTP offline, restart limit exceeded.
[04/07/09 14:15:01]: Restarted HTTP service (11 HTTP events today).
[04/07/09 14:15:01]: MYSQL service is online.

You can take a look at the apache logs, to see what is logged at the same time that this SIM reports "request failed".

bathory, thank you for your reply.

Yesterday I discovered that primary DNS server for several hours was down (secondary was not down). As I understand this was the problem why SIM was restarting Apache every 5 min.

But this problem happends from time to time - SIM restarts Apache almost every day - 2-5 times per day even if DNS servers are working fine.

Probably it's a good idea to change the link which ckecks SIM from:
http://mydomain/file.htm
to
http://111.222.333.444/file.htm (putting IP address instead of domain name).

If your name server is not reliable and that SIM application depends on dns to check servers' availability, then it's indeed better to use the apache IP address.

Regards