I would choose a consistent approach across the entire environment. Both solutions work fine and will remain compatible with most applications. There is a difference in manageability, though.
I go with the short name as the HOSTNAME setting, and set the FQDN as the first column in /etc/hosts for the server's IP, followed by the short name.
I have not encountered many software packages that enforce or display a preference between the two. I find the short name to be cleaner for some applications, specifically logging. Maybe I've been unlucky in seeing internal domains like server.northside.chicago.rizzomanufacturing.com. Who wants to see that in the logs or a shell prompt?
Sometimes, I'm involved in company acquisitions or restructuring where internal domains and/or subdomains change. I like using the short hostname in these cases because logging, kickstarts, printing, systems monitoring, etc. do not need full reconfiguration to account for the new domain names.
A typical RHEL/CentOS server setup for a server named "rizzo" with internal domain "ifp.com", would look like:
/etc/sysconfig/network:
HOSTNAME=rizzo
...
-
/etc/hosts:
127.0.0.1 localhost localhost.localdomain localhost4 localhost4.localdomain4
::1 localhost localhost.localdomain localhost6 localhost6.localdomain6
172.16.100.13 rizzo.ifp.com rizzo
-
[root@rizzo ~]# hostname
rizzo
-
/var/log/messages snippet:
Dec 15 10:10:13 rizzo proftpd[19675]: 172.16.100.13 (::ffff:206.15.236.182[::ffff:206.15.236.182]) - Preparing to
chroot to directory '/app/upload/GREEK'
Dec 15 10:10:51 rizzo proftpd[20660]: 172.16.100.13 (::ffff:12.28.170.2[::ffff:12.28.170.2]) - FTP session opened.
Dec 15 10:10:51 rizzo proftpd[20660]: 172.16.100.13 (::ffff:12.28.170.2[::ffff:12.28.170.2]) - Preparing to chroot
to directory '/app/upload/ftp/SRRID'
From the scanty details you've given us, it sounds to me that you need to tune your I/O scheduler. That can have a significant impact on the lockup effect you're experiencing. I believe CentOS 5.6 uses CFQ. You may get less locking with deadline.
Best Answer
From the comment to the question
The root control group is referenced by a standard group
<name> { }statement where<name>is a single period.