Migration issues

[Alain Spineux]

On Sat, May 3, 2008 at 10:18 PM, DESCOMBES Thierry
<descombes at sb-roscoff.fr> wrote:
> Hello,
>
>  I'm the system administrator of a french research unit (CNRS), and we
>  are using cyrus and postfix, on a server, for 2 years now, without
>  troubles.
>
>  Now, we have bought a DAS (Direct Attached Storage) attached to a
>  dedicated server (with tape backup system...)  and we'd like to use the
>  DAS to store mailboxes.
>
>  My idea was to uninstall the IMAP service on our old mailserver, change
>  its postfix configuration to SMTP relay mails to the new server
>  (attached to the DAS), and install new versions of postfix and cyrus on
>  the new server (where the DAS filesystem are mounted locally).

Yes fine, just configure a "transport" for your domain to your new server.
You can avoid the second postfix configuration by delivering directly your
email trough LMTP by adding something like

  lmtp          cmd="lmtpd -a" listen="your.ip.address.here:2003"

to your cyrus.conf. If you use -a be careful to secure your lmtpd port
with some iptables
rules.


> Do you
>  think this is the best way to do that ? (I have already tested
>  unsuccesfully, exporting files (with NFS) or partition (with
>  open-iSCSI)... but in case of crash, it seems that data integrity is
>  often broken)
>
>  I have tried to configure this setup. On the old server, we are using
>  cyrus 2.2.12 (on Linux), and in the new one, I have installed cyrus
>  2.3.8 (on Linux). So, I have tried to follow the "Upgrading from 2.2.x
>  or earlier" part of cyrus documentation. I have copied the spool
>  directory (rsync of the /var/spool/imap directory), and the db directory
>  (a tar of /var/lib/imap after a cyrus shutdown) from the old server to
>  the new one, created a metapartition directory, launched
>  "tools/migrate-metadata" script... but now, when I start cyrus , it
>  freezes and writes messages in system log files:

imapsync is a nice tool for migration. For now it can sync everything except
annotation and quota. It works like rsync but on top of imap protocol, you dont
need to bother about format conversion.

>
>  kernel: ctl_cyrusdb[26239]: segfault at 00002b7e51a60efc rip
>  00002b5652b30f96 rsp 00007fff59062d60 error 4

You missed something. You have to dump bdb data file on your old
system and restore it on your new system to use the correct library
version on each of them.

You can try to guess what wrong by running something like

# su cyrus -c "strace ctl_cyrusdb -r"

and look in the strace log for the last file opened by ctl_cyrusdb.

>
>  cyrus-master[26233]: process 26239 exited, signaled to death by 11
>
>  What's wrong ? The new server is running a 64 bits linux distribution
>  (the old a 32 bits). Should I try with a version of cyrus build for
>  32bits architecture ?

32bits are still less problematic yet, up to 2Go of RAM 32bits is
probably the best choice,
up to 4Go you can have little benefit using a 64bit system, above 4Go
You have to consider a 64bit
system.

>
>  Thanks a lot in advance.
>  Cheers,
>
>  --
>
>  DESCOMBES Thierry
>  Station Biologique de Roscoff
>  Service Informatique - FR2424
>  Place George Teissier
>  BP 74
>  29682 Roscoff Cedex
>
>  Tel:  (00 33)2 98 29 23 14
>  Port: (00 33)6 63 03 04 74
>  ----
>  Cyrus Home Page: http://cyrusimap.web.cmu.edu/
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>



-- 
Alain Spineux
aspineux gmail com
May the sources be with you