Wysenburg (.RiverCityCanada.com)

October 2004

This computer has been redone a few times. But then it's a server on a private network so it's always under going changes. Previous documentation is here:

October 2000
September 2002
January 2004

This system is a Linux box. It main purpose is a name server and email server for RiverCityCanada.com but it's also a file server for my private LAN. The system is multihomed and sits on the firewall with one NIC in the LAN (local area network) and one in the WAN (wide area network or Internet). The web services (DNS and email) are served through both NIC's while Samba (file sharing) is only bound to the LAN NIC. Click here for a map of the network. The only other thing special about it is it runs NTP and has a GPS receiver as a time source. Check that out here.

The hardware is a dual Celeron 500 with 512MB RAM. The operating system Fedora Core 1. I updated to Fedora from RedHat 8.0 in August 2004 so that I could get critical updates, but about the same time Core 1 was archived. Good grief eh. The latest update was to larger RAID drives. I reconfigured the RAID by using the missing drive method shown in the RAID+BOOT HOWTO's so that I wouldn't loose any data. I documented that here: Changing RAID devices without loosing data.  

RAID

The RAID configuration now is 4x80GB RAID5 mounted as /home plus a mirrored 40GB RAID1 mounted as the root drive. I would have the entire file system RAID5, but Linux can't boot from a software RAID5. I used 2 - 120GB and 2 - 80GB drives. The RAID5 is striped across four 80GB partitions with the remaining two 40GB partitions mirrored. You could loose any one drive here without any data loss.

Linux will boot from a mirrored drive. GRUB actually boots from one of the mirrored drives and the RAID device is passed as a parameter to the kernel (root=/dev/md1). The two partitions used for the mirrored drive are identical so you could add a second item to the boot menu so that it can boot from the other drive. Your system could then still boot if it lost the first drive.

There is a small swap on every drive. Linux will strip across the partitions so the swapping will be faster. Reading from four drives in parallel is faster then from one drive.

[mm@wysenburg mm]$ /sbin/swapon -s
Filename        Type         Size      Used     Priority
/dev/hde1       partition    257000    1228     1
/dev/hdg1       partition    257000    1212     1
/dev/hdi1       partition    258008    1232     1
/dev/hdl1       partition    258008    1232     1

Samba

Nothing special about Samba. It's version 3.0. It's only available on the LAN NIC and I use it to backup my workstations and other file storage. I joined the Samba system to my Windows AD so it's available to anyone that logs on to the AD network.

On another network with Samba acting as a PDC for the domain, I installed a Windows XP system and it broke my Samba configuration. To fix it, I installed dual Samba servers on the computer, one acting as a PDC and the second just a member server. I documented the method here.

Other Servers

Linux comes with a pile of other services. A couple that I haven't mentioned yet are ftp, sendmail and bind. Sendmail is setup to service the email for RiverCityCanada.com, marien.ca and slsa.sk.ca. It also acts as a redundant email server for DigitalMapping.sk.ca and PetersSurveys.ca. The name server (bind) is one of three that I have. This one acts as the slave for most of the Internet domains I administer.

NTP is also running on this computer. I compiled and installed version 4.1 and updated a driver to run my Tripmate GPS reciever. I have a small network of time servers that keep two Win2000 networks in sync. Check that out here.

I run two SETI's on here. One on each Celeron 500. I also run one on the dual PIII 500. I keep track of them with a program I wrote. It's available from CNET or here.