Web Hosting Talk : Web Hosting Main Forums : Hosting Security and Technology : Apache failure: unable to find IPv4 address?

[ElricM]

I've been getting the following error periodically I presume when Apache tries to restart:


[alert] (EAI 2)Name or service not known: mod_unique_id: unable to find IPv4 address of "<my server>"


The result is Apache fails to startup and all my domains are down until I notice the problem (or someone emails me). Happened again after midnight, I didn't notice until 7am. I tried to compensate with a Webmin service monitor but that doesn't work.

Can anyone tell me why this problem occurs and what I can do about it?

System is RHEL3 (all errata/packages up to date) and Plesk 7.5.3

[FirmbIT]

What do you have in your /etc/hosts file currently?:

cat /etc/hosts

[ElricM]

Oh oh... only localhost:

127.0.0.1 localhost.localdomain localhost

I have 2 IP addresses on the machine. Do I need to put them both in there? Same for all the domains? As you can tell, I'm very new to linux.

Is it good enough to just list the server?

eg,

127.0.0.1 localhost.localdomain localhost
111.222.333.1 hostname hostname
111.222.333.2 hostname hostname

[FirmbIT]

You should only have 2 lines listed. One of them should be 127.0.0.1 and to the right of it should be localhost. The second line should have your servers IP address and to the right of it should be your servers hostname beside your servers full hostname + domainname (example localhost.domain.com and hostname).

To find out your hostname type hostname in shell.

When done editing, save the file and restart apache.

[ElricM]

Thanks very much for the reply.

[johnc7]

I was having a similar problem on an older Fedora Core 3 (Linux version 2.6.12-1.1381_FC3) box. Curious as to why this would suddenly become a problem after not having a second /etc/hosts file entry for the hostname since the machine was first online (years ago). Seems unusual.