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I recently set up a new file server. It contains three 1 terabyte drives configured in a RAID 5 array but with RAID 1 for the boot partitions so in the event of drive failure the system could still boot.

Essentially you need to go through a normal installation process and make sure you choose a couple of things during parition setup. I split each of the 3 drives in to two partitions, one 200MB, and the other partition the remaining disc space. This is what I had:
sda1 = 200MB
sda2 = 9800MB
and the same for the other drives.

Set all sda1 partition to be ext3 and bootable and mounted as /boot, set sdb1 and sdc1 partitions to be Linux Software Raid, bootable, but not mounted. Configure the RAID and create a new RAID device, tell it to use three devices and add to it sda2, sdb2, and sdc2.

When I returned to the partition menu I configured md0 as a partition for a logical volume group. I then configured LVM and created logical volumes for /root, swap, and /home. Returning to the partitioning menu I formatted these and selected their mount points and installed the system.

Following system installation I went about creating a RAID 1 array for sda1, sdb1, and sdc1. First thing was to create a new array using mdadm and the two paritions we haven’t yet assigned:
# mdadm --create /dev/md1 --level=1 --raid-disks=3 missing /dev/sdb1 /dev/sdc1

Make a filesystem on our new RAID device:
# mkfs.ext3 -m 0 /dev/md1

Save the new configuration in to mdadm’s config file:
# mdadm --examine --scan >> /etc/mdadm/mdadm.conf

Edit mdadm.conf and remove the duplicate entry at the bottom:
# vim /etc/mdadm.conf

Mount the new RAID device so we can copy data to it:
# mkdir /media/md1
# mount /dev/md1 /media/md1

Copy over the boot partition to the RAID device:
# cd /boot
# cp -dpRx . /media/md1

Edit fstab and replace /dev/sda1 with /dev/md1:
# vim /etc/fstab

Edit mtab and do the same:
# vim /etc/mtab

Unmount /boot, change it’s system type and add it to the RAID array:
# umount /boot
# fdisk /dev/sda
Command (m for help): t
Partition number (1-4): 1
Hex code (type L to list codes): f
Changed system type of partition 1 to fd (Linux raid autodetect)
Command (m for help): w

# mdadm --add /dev/md1 /dev/sda1

Configure GRUB so that it can boot from any hard drive:
# grub
grub> device (hd0) /dev/sda
grub> root (hd0,0)
grub> setup (hd0)
grub> device (hd0) /dev/sdb
grub> root (hd0,0)
grub> setup (hd0)
grub> device (hd0) /dev/sdc
grub> root (hd0,0)
grub> setup (hd0)
grub> quit

# update-initramfs -u

Change all occurance of (hd*) to (hd0) in the file /boot/grub/devices.map.

That should be all - good luck with the reboot!
# reboot

Installing Netatalk from the repositories means that when you connect using a Mac client you will be warned that you are going to send your password in the clear. Obviously this isn’t great for security, and being prompted every time you want to connect is annoying. This occurs because Netatalk in the Ubuntu repositories is compiled without SSL support (SSL is what handles the encryption).

The key to getting this to work is to get the Netatalk source code and compile it yourself. Don’t worry, it’s been done hundreds of times before and if you follow this tutorial closely you should be fine.

The commands written always start with a dollar sign ($), you should not type this, it just indicates the commands should be typed at a standard user prompt in the terminal.

First off it’s a good idea to switch to your home directory:
$ cd ~

Make a new directory to hold the hundreds of small Netatalk files:
$ mkdir netatalk

Ensure you have essential development libraries and tools installed:
$ sudo aptitude install libdb4.2-dev libslp-dev autotools-dev devscripts cracklib2-dev dpkg-dev libssl-dev

Change in to the newly created directory:
$ cd netatalk

Install the netatalk source code:
$ sudo apt-get source netatalk

Install all required dependencies for netatalk:
$ sudo apt-get build-dep netatalk

A new directory called netatalk-2.0.3 should have been created, change in to that directory:
$ cd netatalk-2.0.3

Compile Netatalk with the SSL option:
$ DEB_BUILD_OPTIONS=ssl sudo dpkg-buildpackage -us -uc

Install the finished product!:
$ sudo debi

Initially I had set a mail account with a quota of 200000, or roughly 200MB. The user complained of a full mailbox, despite using Plesk to up the limit to 2GB, and then unlimited the account continued to bounce emails saying:
"Recipient's mailbox is full"

I found people complaining of a bug in version 7.5 of Plesk, but it seems this is also present in 8.3. The problem, I discovered after nosing around the config files of the server, was that any changes I made in Plesk weren’t saved. Ultimately I found the limit in the config file remained at 200MB, despite numerous changes. The quota config file is located at:
/var/qmail/mailnames/example.com/username/@mbox.quota

Manually edit that file so it has the quota you want. I like to use vim:
vim /var/qmail/mailnames/example.com/username/\@mbox.quota
(run this as root)

After editing, save the changes, and you won’t need to restart any services or the server. Changes should take effect.

Note, that this was performed on a CentOS 5 installation, so paths and instructions may vary slightly on other systems.

I recently found that sending emails via my server was painfully slow. After further invesitigation in to this issue I discovered that the server was performing reverse-DNS checks on client IPs. These were slow because they often didn’t work and had to wait for a timeout. The solution is to turn of reverse-DNS checking on the server by editing a config file as follows…

The modification must be made to the /etc/inetd.conf file:

smtp stream tcp nowait root /path/to/qmail/bin/tcp-env tcp-env -Rt0 ...

smtps stream tcp nowait root /path/to/qmail/bin/tcp-env tcp-env -Rt0 ...

It is necessary to restart inetd in order for the changes to take effect:

# kill -HUP `cat /var/run/inetd.pid`

Note, /etc/inetd.conf may be overwritten and the options you added will be removed if you make certain changes through Plesk CP, for example add MAPS server.

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I have recently had a hard time getting FreeBSD to ‘play ball’ by sharing it’s resources via AFP. I have compiled this guide to help others through the traumatic experience. I was using FreeBSD 6.2 release and Netatalk 2.0.3 from ports. Though I have heard it works on 6.1 and 6.3. (more…)