September 12, 2008 – 2:29 am
Seriously… Unrecoverable crash. Oh well, I was getting tired of fighting with it anyway and now I can move on. Instead of trying to rebuild it I’m just gutting the useful parts out of it, and several other old computers. I’m sending it all away and moving on to what I’ve been wanting to do anyway, which is actually a couple of different things. I really want to pursue my philosophical/spiritual studies and I may start posting about that, and I also would like to write a role playing game. I’m thinking a post-apocalyptic game with serious fantasy elements and a heavy spiritual twist…
I also wouldn’t mind getting back to writing short stories again though my creativity in that regards has seemed to be somewhat lacking for the last several years now.
Anyway, whatever I end up doing is what I end up doing so we’ll just have to see what happens now. 
August 1, 2008 – 11:43 pm
Ouch!! Today I was installing and setting up kerberos, trying to set things up so that I could log into any of the computers here with SSH and no passwords. Anyway, there came a point where I decided to reboot the server, it was the first time I had rebooted in a while, and when it came back up it was totally screwed…
DNS was timing out, SSH with an IP address was timing out, and logging in on the physical console seemed to be totally non-functional. Eventually I gave up and went to smoke a cigarette, when I came back I was logged in, but then sudo -i took nearly five minutes to switch to root, a quick tail /var/log/syslog showed many tens of thousands of ‘time went backwards’ messages being logged per second. I turns out that there is a bug that has been around for a while from the looks of it. I followed the suggestions there, adding: “xen.independent_wallclock=1″ to /etc/sysctl.conf in each DomU and “clock=jiffies” in the DomU’s .cnf file in the “extra” section. I also installed ntp on each domU and set them to sync with the NTP server that runs on dom0. Read More »
Okay, this took a lot of trial and error testing. There seems to be two ways of getting information passed to the installer when netbooting, and both have different strengths and weaknesses. First we have kickstart files, which seem to be somewhat lacking in support in ubuntu. Then we also have preseeding, which is supported much more thoroughly and quite flexible. Unfortunately, preseeding can anly affect things after the network has been configured, (unless you put it in an initrd image which I never figured out how to do), so it leaves a few questions at the beginning of the install still needing to be answered. On the flip side, kickstart will cause the network to be configured right off the bat and can be used to get rid of even the first questions, but it has no support for quite a lot of options and so falls somewhat short of being a reliable solution. After many test installs I have gone with the idea that a combination of the two technologies is the only viable option, using kickstart only to answer the questions that preseeding cannot and using a preseed file to take over from there. Read More »
By Krusty Ruffle
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Posted in Ubuntu
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Tagged apt-mirror, automated install, GRUB, hostname, install server, kickstart, Linux, netboot, preseed, PXE, server, Ubuntu
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I was originally thinking of using apt-cacher for this, and I’m sure it would be a more bandwidth friendly solution, but I had some issues with using it for local installs and had already used apt-mirror to build an entire mirror before I figured out what the problem was. Considering that I already had 30 some gigs of mirror sitting there I went ahead and stuck with the apt-mirror solution. 
I had also planned on using a separate Xen DomU to set this up on, but as both of these work through the Apache web server I went ahead and modified the LAMP server DomU to also contain this. If your running this in a Xen virtual machine, and you haven’t created the virtual machine yet then this one needs to be big. Apt-mirror takes a little over 26 gigs for the main, restricted, universe, and multiverse repositories, and that’s without mirroring the source repositories. If you also mirror other repositories you could very easily go over 30 gigs, and I have no idea how big the source repositories would be but I would guess they are bigger than the non-source equivalents. If you have already made the virtual machine then you have a couple of choices. You could make another volume and set it up so that it mounts in the place you want your repositories to be mirrored, or you can extend the volume you have set up for the virtual machines root drive, or var if you used multiple volumes. I’ve used the second option and will not be covering the first one here. As always, most of this requires root access, so sudo -i might be a good idea, and any commands I post will need to be modifies to fit your naming schemes etc… Read More »
By Krusty Ruffle
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Posted in Ubuntu
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Tagged apache2, apt-mirror, DHCP, DNS, firewall, FQDN, install server, Linux, netboot, PXE, server, Ubuntu, ufw, virtual machine, xen
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Today I’m posting about LAMP (Linux Apache MySQL & PHP) servers. I’m going to set one up with HTTP (Hypertext Transfer Protocol) on port 80, HTTPS (Hypertext Transfer Protocol over Secure Socket Layer) on port 443, user directories that have access to both protocols, and SFTP (SSH File Transfer Protocol) for those users. I’m doing this in one of my Xen virtual machines and using UFW (Uncomplicated Firewall) to apply packet filtering to the server. As always, most of this has to be done as root, so I’m using SSH to connect, then doing sudo -i to get a root terminal.
One problem I had with this was the hostname/FQDN (fully qualified domain name) of the machine. I’m not sure why, but I had a couple of files that were wrong for this, and it really screwed up the SSL (Secure Socket Layer) stuff for the secure server. A correctly configured machine will return only the hostname, without the domain name attached with the hostname command, hostname -f will return the hostname.domain.name all attached in one string, and dnsdomainname will return only the domain.name portion. If these commands do not return the expected values then something needs fixed. To do this with file editing you can open up the /etc/hostname file: Read More »
By Krusty Ruffle
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Posted in Ubuntu
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Tagged apache2, firewall, FQDN, hostname, install, Linux, OpenSSH, OpenSSL, server, SFTP, Ubuntu, ufw, user directories, virtual machine, xen
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