Install Ubuntu Server for Use as a Simple Router (Stage 1)

These instructions, which will come in several posts, are from start to finish to set up a simple router that serves out DHCP addresses on the internal network card. I spent a lot of time getting this figured out, as I am not an expert at networking (yet--I will begin working on my CCNA after I finish studying for my A+). If you already have a working installation of Ubuntu Server you may skip this post if you'd like.



As some background on exactly what I'm trying to accomplish here: I built this for work, so your setup may vary. Our setup includes many school sites that are physically separated from each other, but are connected via 100Mb fiber from a service provider back to our Technology Office, which has a Cisco 1841 that already contains all the routes setup to the site routers, which all are setup to serve out DHCP on their own subnet. The reason I was looking into this is to have a cheap, but reliable, replacement for our 15-year-old Compaq servers running Netware 6.5 that are acting as routers. Because of their poor processing speed the Compaq servers are slowing down access from the sites to the rest of the network, and replacing them is definitely a good idea. We are not going to be using the Ubuntu Server that I am describing here in production; however, I did test it out at a site and it did work well.

Prerequisites:

• Ubuntu Server CD (download and burn from ubuntu.com/server)


• Computer with two network cards installed to use as a router


• Have IP addresses and subnets planned out


• Some time and a little patience

Install Ubuntu Server

1. Boot off of Ubuntu Server CD


2. Choose English as language


3. Select 'Install Ubuntu Server'


4. Choose English for default language


5. Choose United States for country


6. Choose 'No' for detecting keyboard layout


7. Choose USA for origin of keyboard


8. Choose USA for Keyboard layout


9. It will detect the hardware to find CD drive, then scan the CD for installation packages etc, then load the components it needs to run the install, and detect network cards.


10. If you already have two network cards installed, then it will ask you which one you would like to use as the primary network interface. Stick with eth0 as the primary. The installer will automatically configure the card with DHCP


11. Enter in the hostname here...for this tutorial's purposes I used ubuntutest.


12. It will then setup the clock, and should automatically detect your time zone. Choose 'Yes' if it is correct.


13. Partitioning time! Ok, so now what we want to do here, is use the 'Guided - use entire disk and set up LVM' even though we won't use LVM, it just is nice to have in case in the future we do decide to do more with these.... make sure the correct entry is selected and press enter.


14. It will ask you what disk you want to partition, in systems with only one disk this is easy. Obviously it will erase everything on the disk so make sure you really want to do this. Select the correct disk and press enter.


15. Do you really want to make the changes? Press the left arrow to move over to 'Yes' then hit enter.


16. it will ask you the size of the 'volume group'...just go with the defaults.


17. The installer hasn't actually written any changes to the disks yet, so it now asks you if you really want to make a long-term commitment to the options you have previously selected. You may sleep on this if you wish, or, if you're daring like me, take a deep breath, press the left arrow over to 'Yes', close your eyes and hit enter. Count to 30, open your eyes, and the partitioner should be done. Boy that's stressful.


18. So now it will go through and install the base system...you can just chill here for a while, grab a cold soda...maybe some Doritos...mmm....cooler ranch Doritos sound realllyyy good....or go play minesweeper or maybe even get some real work done here. Or, if you really want to be an overachiever, go ahead and plan out what IP address, subnet masks, DHCP range, etc you want to configure this server with. I know I did. But seriously, this does take a little while so you may want to take a quick break, walk around outside and grab some fresh air, cause you may be here a while practicing your commandline-kung-fu to complete the rest of this setup.....


19. Okk....now that the base system is finished installing, it's time to select a username. Adhering to my principles of making life easy for everyone, I chose administrator as the full name of my user.


20. Username for the account? Make life easy: administrator


21. Time for a password! Because this is not going to be a 'critical' system per se (i.e. is not on the edge of our network and is only going to be routing and serving out DHCP) I wouldn't be too concerned about security, so choose a password that is easy to remember.


22. Verify the password.


23. It will probably warn you about using a weak password. Yeah, I know. hit the left arrow and choose 'Yes'.


24. We do not want to encrypt our home directory. Choose no and move on.


25. The installer is going to run through some update stuff and grab some packages...and ask you to choose a proxy. We don't have a proxy, so just hit enter through this (blank is no proxy).


26. I haven't messed around with the automatic update feature...figure it's probably best just to leave it be. I chose 'no automatic updates'


27. It's gonna grab some software...and this is where it gets fun. Software selection...because we're only wanting to do two things with this computer (routing and DHCP) the only thing we want to select here is OpenSSH server. Down arrow to it, press space to select (notice the star in the brackets now? Yeah, pretty cool), and hit enter to continue. What OpenSSH does is installs and configures the OpenSSH server so we can log into this machine remotely (kinda like the Adrem Console, except so much better and free). Of course, in order to do this I use Putty (google it...) but there are plenty of ways to connect to an SSH server...so pick your poison.


28. Ok, so more configuring and updating the system...woohoo. Finish off that bag of doritos, grab another soda (woooo sugar rush! haha) and chill. If you want to really challenge yourself, try watching the package names as they're configured and installed...see if there are any that you recognize. You'll be using some of them later :)


29. Now it's going to install GRUB boot loader. It will probably ask you if you want to install GRUB to the master boot record of the hard drive....choose 'Yes', because we're not building a dual-boot system here or anything fun like that.


30. Now the installer will finish the installation, and eject the CD. Go ahead and remove the CD, and choose 'continue' to reboot into your new server installation.