Archive for kerrighed cluster

kerrighed cluster

Posted in general with tags , , , on July 21, 2008 by deadwait

So , its feels like a real long time since im writing anything, i was totally busy for almost the whole last month just trying to install Kerrighed ( http://www.kerrighed.org ) , which is a SSI –> single system image cluster. Now all i wanted was dynamips to run on two or more machine’s, Ok so i know that i can start the hypervisor separately on other machines and use the combined processing power anyways, but my idea was to allow it to be accessible remotely, so i thought i would build a cluster on which dynamips would run and use all the cpu power of the entire cluster.

Now  i have never worked on any clustering software before now new much about it, turns out there are so many different types of clustering software available, the best in terms of popularity, ease, support, documentation  “seemed” to be openmosix, but as of March 2008 the project is dead, closed by its founder, Moshe Bar. Now reading about openmosix gave me little knowledge about SSI cluster’s, meaning suppose i put up 4 machine’s each with 4 processors and 4 gb ram and i set them up in a SSI cluster, what i get is something looking like one machine with 16 processors and 16gb ram, its true, i was able to do half the size of that cluster ( because that’s how many machines i had in my hand to test ), now there might be many out there who have seen this before, but for me, after a really long time  I saw magic! . When i actually finally managed to get the cluster up and top command showed 8 cpus and 4gb ram, ( cluster of two pc’s quadcore with 2gb ram each) , i just kept staring at it in awe, I swear it was so sexy i left it like that for one and a half day before i actually started testing dynamips on it.

The clustering software i finally ended up using was kerrighed, which  supports one of the newer kernels that is 2.6.20 the next in line would be openssi, which i think supports 2.6.9 or 2.6.12 im not sure right now. installing it took me 3 weeks that too after i gave up installing it on the quadcore machines and tried it on some p3 machines with realtek rtl8139 drivers. the next post will be an entire document on how to install kerrighed on the debian lenny system. The guys on the mailing list of Kerrighed as well as the developers of kerrighed are very helpful and were not irritated at all by my newbie questions, in fact i came out of it knowing a little more about linux, eg: i had never recompiled a kernel before. 

Well did dynamips work? NO! , that hurt, but then it’s ok doing the entire exercise was fun, oh and the reason dynamips did’nt work was kerrighed does’nt support migration of multithreaded processes yet, i did check the migration with a program called cpuburn and it worked fine.  

Well hopefully  i might get some test machine’s again and i could work out something , i also wanted to test cacti on it and see if that’s a feasible option. hmm lets’s see.