I've recently been asked to investigate the possibility of using our 2 Samba
fileservers (strictly) in a manually-enabled symmetric failover configuration
for read-only file shares.
Using rsync :) I've managed to replicate the predominantly static
filesystems
between our two Unix servers. Now, I'm testing a script which starts a
second
set of nmbd and smbd procs (in daemon mode) by specifying an alternate
configuration file. My initial tests seem to indicate that this may actually
work.
At our site, we use Version 1.9.18p10, server (proxy) authentication to an NT
PDC, WINS, and limit nmbd to non-master-browser/non-WINS-server roles.
We're
not concerned with print services, just file services.
The changes to my original smb.conf as well as the alternate smb.failover.conf
files on both servers are summarized below:
smb.conf
--------
bind interfaces only = true
interfaces = primary.interface.ip.addr/mask
smb.failover.conf -- same as smb.conf except for:
-----------------
netbios name = other_hostname
interfaces = virtual.interface.ip.addr/mask
replaced primary shares with directories of replicated data
When a primary server fails (disk crash, system board, whatever), I can login to
the other system and run a script which will ideally come to the rescue:
1) ifconfig a virtual interface (such as eth0:1) with the same IP addr. as the
failed server
2) nmbd -D -s smb.failover.conf
3) smbd -D -s smb.failover.conf
and (hopefully?)... viola!
How will smb clients react to this? Will the sudden ethernet (MAC) address
change cause any hardship to NT clients? How about lock (var) directories, can
they be shared between the two sets of server processes? Any other caveats that
I'm overlooking? Am I in violation any major Samba dogma? Any comments
would
be greatly appreciated.
Please, also reply by direct email, as i am not a regular subscriber to this
list.
TIA, John
