SAN with Linux Cluster and CLVM: Is it Necessary?


To answer the title of this post in one word: No. But as with all things computer related, that “no” needs to be followed by the caveat: “Well, it depends upon your needs.” From what I’ve seen, Linux clustering was designed primarily for high-availability services, with only a secondary effort to share disk resources across nodes. I have tried — and would never use in production — Linux clustering services for a VM host cluster. I know other people have done it and will continue to do it, but a properly configured (and managed) VM cluster does not need true clustering. (Again, “depending upon your needs”). Linux clustering requires fencing. (It didn’t always, but now it does). Fencing is a … Continue reading

Finding Out the IP Address of a New Piece of Tech from eBay


I’ve been through this many times over, and thought I would share:   I just bought a pair of HP Storageworks 4/8 SAN (AKA: Brocade Silkworm 200E) switches off of eBay.  They were listed as “powered up / as-is” by the seller, but the price was too good not to take a risk on them working properly. Of course, they came with no documentation, and not even a label to identify the IP address they held in their original home.  (I have had luck with other items where the IP and even login/password were labelled onto the front of the case). Most times, the following will work flawlessly: Connect your new piece of tech’s management interface (in this case, we’ll use … Continue reading