On 3/24/2011 8:04 AM, Les Mikesell wrote:
On 3/23/2011 10:45 PM, Todd Cary wrote:
I plan to make my current Centos 4 HD a slave and install Centos 5.5 on a new HD (master). Then comes the challenge of of moving all of my /home/"user" data to the new master. I have some preliminary questions:
Is this a good strategy for installing Centos 5.5: keep the Centos 4 on a slave disk?
It's a reasonable approach if you only have one computer. Just pick the new 1st drive only (and remember your old one is already on the 2nd controller) in the installer.
Will the Centos 5.5 detect the slave disk (Centos 4)?
It will see it at the hardware level but not do anything with it. You'll need to figure out the device name or label for the partition (and Centos5 will probably call it /dev/sd? instead of hd) and mount it somewhere. You should also be able to configure a dual boot if you wanted.
For now, the Centos 4 disk is disconnected...playing it safe. Later I'll activate the HD as a slave.
Is there a way to move the users, groups and passwords from one disk to the new Centos 5.5?
The files /etc/passwd, /etc/shadow, /etc/group, and /etc/gshadow have this information. But don't just copy them over. The accounts below uid 500 belong to the system and may be different between versions or depending on the installed software. You can edit your old entries that you have added into the new corresponding files. Or, for a small number of users, just 'adduser -u uid login_name', then 'passwd login_name' to set the password.
Actually, there are less than 12 users, as I recall, so manually setting them up will be the easiest.
IT departments must have servers go down or want to install a new version of Linux and have the same challenges.
Normally if there are enough machines/users for this to be a problem, there would be a central authentication mechanism like LDAP or active directory set up. Servers for things other than direct login or file mapping often don't have many real users, though.
Yes, that makes sense. Of course, what happens if there is a need to bring up a new box for the authentication?
Onward....
Todd