Zimbra Incremental Migration: an experience

Some days ago, I managed to migrate our company's Zimbra mail system to a new server.  Since there were so many messages to move, the migration was a hard work, and caused a lot of troubles.

A brief description of the task:

• The old server: CentOS 5.5 x86_64, ZCS 7.2.0
• The new server: CentOS 6.3 x86_64, ZCS 8.0.0
• Mail accounts: 1500, messages: 4 millions, storage: 600 GB
• Bandwidth between two servers: 100 Mbps

I followed the method described in ZxBackup: Incremental migration with ZeXtras Backup.  The process comprised the following steps:

1. Backup of all messages on the old server: about 4 million items, backup time: 3 days.
2. Synchronization of backup data to the new server: data size: 320GB, files: 6.4 million, transfer time: 1 day.
3. Restore of old messages on the new server: restore time: 5 days.
4. Incremental backup and restore recent messages since last backup
5. Switch of the mail flow to the new server
6. Incremental backup and restore recent messages since last backup

Android ICS L2TP/IPSec `malformed payload in packet' error

When you try to connect to an OpenSWAN L2TP/IPSec PSK using an android device of version 4.0.x (Ice Cream Sandwich), you may get the following repeated errors:

Nov 7 15:13:42 vpnserver pluto[20906]: packet from 200.143.118.22:500: next payload type of ISAKMP Message has an unknown value: 133
Nov 7 15:13:42 vpnserver pluto[20906]: | payload malformed after IV
Nov 7 15:13:42 vpnserver pluto[20906]: |
Nov 7 15:13:42 vpnserver pluto[20906]: packet from 200.143.118.22:500: sending notification PAYLOAD_MALFORMED to 200.143.118.22:500

and will get a connection timeout.  That is because of a bug in ICS.  Android ICS seems to mess up the payload which causes this error: byte 7 of ISAKMP NAT-OA Payload must be zero, but is not (see rfc 3947).

There has been a bug report about this.  It should have been fixed in Android 4.1.x.   For 4.0.x (ICS) device, fortunately, there is an OpenSWAN workaround available at:

http://people.redhat.com/pwouters/osw/openswan-2.6.38-android-ics-natoa.patch

To resolve your issue, download this patch and recompile your openswan.  If you compile openswan from SRPMS, make sure to change openswan.spec, add `-DSUPPORT_BROKEN_ANDROID_ICS' to make option `USERCOMPILE' in your openswan.spec, like this:

%{__make} \
USERCOMPILE="-g %{optflags} -fPIE -pie -DSUPPORT_BROKEN_ANDROID_ICS" \
......

Using `cvsd' to setup cvs pserver

CVS was designed to use `xinetd' to startup service. But now most Linux distributions do not install xinetd by default, and configuration of CVS is somewhat complicated. `cvsd' is a wrapper program for CVS in pserver mode, it can startup CVS as a standalone daemon, under a special uid/gid in a chroot jail. It is relatively easy to use cvsd and its configuration file to setup CVS repositories.

In this article, I will describe how to setup a cvs pserver step by step.

1. Installation of cvsd package

For RPM-based distributions, you may download precompiled RPMS from this site:

cvsd-1.0.14-1.i386.rpm
cvsd-1.0.14-1.src.rpm (source)

For other distributions, you may download source tarball here, compile and install it yourself.

Setup of VSFTPD - another approach

If you are hosting several web sites, for security reason, you may want the webmasters to access their own files only. One of the good way is to give them FTP access by setup of VSFTPD virtual users and directories.

In my last article, I described how to setup VSFTPD virtual users. In this article, I will describe another approach to setup VSFTPD, it needs real users on the system.

1. Installation of VSFTPD

For Red Hat, CentOS and Fedora, you may install VSFTPD by the command

# yum install vsftpd

For Debian and Ubuntu,

# apt-get install vsftpd

Setup of VSFTPD virtual users

If you are hosting several web sites, for security reason, you may want the webmasters to access their own files only. One of the good way is to give them FTP access by setup of VSFTPD virtual users and directories. This article describes how you can do that easily.
(See also: Setup of VSFTPD virtual users - another approach)

1. Installation of VSFTPD

For Red Hat, CentOS and Fedora, you may install VSFTPD by the command

# yum install vsftpd

For Debian and Ubuntu,

# apt-get install vsftpd

Installation of CentOS on a server with a SmartRAID V controller

We are going to reinstall Linux on an old server with a SmartRAID V controller. Since CentOS can be updated easily using 'yum', we decide to use CentOS 5.1. There are some difficulties in installation, but we can bypass them and accomplish it successfully.

The basic parameters of the old server:

• 2 x Intel(R) Xeon(TM) CPU 2.40GHz
• 4G Memory
• Adaptec (formerly DPT) SmartRAID V Controller
• 6x 36704 MB SCSI disks
• Intel Corporation 82545EM Gigabit Ethernet Controller
• ATAPI 52X CD-ROM drive

The main points of installation are described below: