Migrating Samba Server and Users in CentOS 6

Migrating Samba Server and Users in CentOS 6

To migrate Samba users from one server to another, we will be needing to migrate the following -

1. /etc/passwd
2. /etc/group
3. /etc/shadow
4. home directories and shared directories
5. /etc/samba
6. /var/lib/samba

We assume that we have two servers: old-server (192.168.10.10) and new-server (192.168.10.20). Some of the commands are need to be run in the old-server and some need to be run in new-server.

Old Server:

Backing up users, groups and passwords

[root@old-server ~]# mkdir /root/move [root@old-server ~]# export UGIDLIMIT=500 [root@old-server ~]# awk -v LIMIT=$UGIDLIMIT -F: '($3>=LIMIT) && ($3!=65534)' /etc/passwd > /root/move/passwd.mig [root@old-server ~]# awk -v LIMIT=$UGIDLIMIT -F: '($3>=LIMIT) && ($3!=65534)' /etc/group > /root/move/group.mig [root@old-server ~]# awk -v LIMIT=$UGIDLIMIT -F: '($3>=LIMIT) && ($3!=65534) {print $1}' /etc/passwd | tee - |egrep -f - /etc/shadow > /root/move/shadow.mig

NOTE: Please click here for explanation on what the awk command does.

Time to move the home directories using rsync

[root@old-server ~]# yum install rsync [root@old-server ~]# rsync -av -e ssh /home/* 192.168.10.20:/home/

IMPORTANT: It is vital to preserve the permissions of the files/directories. Although there are many ways to do this, rsync is the easiest possible way.

NOTE: Shared directories can also be migrated the same as home directories. rsync can take care of it.

New Server:
First, we copy the /root/move directory from the old server to the new server.

[root@new-server ~]# scp -r 192.168.10.10:/root/move /root

IMPORTANT: Please backup you passwd, group and shadow file before the next step.

Then, we merge the *.mig files to the actual passwd, group and shadow files

[root@new-server ~]# cd /root/move [root@new-server ~]# cat passwd.mig >> /etc/passwd [root@new-server ~]# cat group.mig >> /etc/group [root@new-server ~]# cat shadow.mig >> /etc/shadow

IMPORTANT: Please make sure to use >> (append) and not > (redirection)

Now, it's time to prepare samba

[root@new-server ~]# yum install samba samba-common [root@new-server ~]# rsync -av -e ssh 192.168.10.10:/etc/samba/* /etc/samba/ [root@new-server ~]# rsync -av -e ssh 192.168.10.10:/var/lib/samba/* /var/lib/samba/ [root@new-server ~]# service smb start; chkconfig smb on [root@new-server ~]# service nmb start; chkconfig nmb on [root@new-server ~]# netstat -tulpn

If samba is up and running, netstat would show it.

This way, a Samba server with all it users can be migrated to a new system. Shutdown the old server and check whether the domain or shared directories can be used.