jmn@power.berkeley.edu (J. Mark Noworolski) (11/16/90)
(for those of you who saw this under a different title, and as a follow-up, I've cancelled those two articles-....sorry). Our research group will soon be getting about 4-6 decstations. The plan is to use redundancy as backup since each machine will have a big disk- but there will be no tape drives. I am the one who will be maintaining them. My question is, what is the best way to set them up? Should I have one fileserver? In particular this is what I have been thinking: 1. Avoid using one machine as a fileserver- it will be unfairly loaded, and if it breaks then our whole cluster will be toast. An advantage is that administration will be headache free (until the inevitable disk crash). 2. Set up individual accounts on different machines. So let's say I have four users (a,b,c,d) and four machines. Then I make user a's home directory on machine 1, user b on machine b, etc. Now I nfs mount the user directories to each machine. So that if user a logs in to machine b,c, or d he will see his home directories from machine a by nfs. Any comments on this approach? In our configuration, _most_ of the time it will be fairly easy to predict who will be logging in to which machine most of the time- so I think this stands a chance of working. What scares me about this approach is maintenance- I think it will be a real pain to addusers on each machine individually. 3. Backups. There are two problems here- one is to back up the operating system and another to do the user directories. We do not plan to use a tape drive (since one was not purchased), but redundancy instead. Any comments? a) operating system- Perhaps the best idea is to have all updates to be done on one machine and have those propagate to the other machines overnight via cron and timestamp comparisons. Has anybody done this? I can see a problem trying to figure out which files to propagate, and which ones not to (log files, news spools, etc.). b) user accounts. This one I don't think is a problem- just use cron to do a tar and copy via nfs to another machine in a circular fashion. 4. Adding other machines to the cluster may be a bit of a pain if they are ever purchased. I would really appreciate any comments about these ideas. I would love to hear from anybody who has done something similar. Gee, I would really like to get some examples of administration software for this approach also. Thanks in advance, mark -- "There's a really fine line between clever and stupid" Nigel- Lead Guitar (Spinal Tap) jmn@united.berkeley.edu, or jmn@power.berkeley.edu