CentOS
From ConShell
CentOS is a derivitave of Red Hat Enterprise Linux, versions 2, 3, 4 and now 5.
So while most of the Red Hat information applies equally to CentOS, there are certain CentOS-specific things worth explaining.
CentOS is a good choice if you don't want to (or can't afford to) pay for support from Red Hat. If you choose to use CentOS your support options include:
By and large, though, you are on your own ... so pull up your bootstraps and dig in!
yum vs. up2date
Another consideration is the use of yum vs. up2date for patching the system. I believe yum is a better choice, it is more intuitive and easier to learn. However, newer versions of up2date have the RPM rollback option, which is neat.
yum-utils for old kernel cleanup
Over time your system may pile up a heap of kernels. Since you can only run one kernel at a time, it makes sense to not keep more than 2 (current and one older/backup). Here's a tip from Bart Schaefer explaining how to prune the kernel list down to just two.
yum install yum-utils package-cleanup --oldkernels --count 2
Instruct yum or rpm to save old packages
This is handy when patching your system and want to keep the old (replaced) packages around for a time. Specify this in /etc/yum.conf
tsflags=repackage
The RPMs that yum replaces (e.g. during yum update) will be repackaged and put into /var/spool/repackage/
The other way to do this is to specify the following in your /etc/rpm/macros file. If the file does not exist simply create it:
%_repackage_all_erasures 1
Kickstarting CentOS-5 and DHCPv6 timeout
There is a looooooonnnngggg (1 minutes) DHCP timeout while it tries to get a DHCPv6 address (not likely).
Someone suggested adding "noipv6" kernel arg when booting.
Yes it works!
See Also
