June 2008 - admins-discuss@lists.redbrick.dcu.ie

[Admin-discuss] Murphy (long mail warning - sorry)
by Andrew Martin 14 Jul '08

14 Jul '08

Hi all, There's been talk about what's going on with murphy recently, and, we're not quite sure yet, so figured this'd be a good place to discuss it. At the moment, it's sitting there idle, with Solaris 10 installed. Linux was taken off it for a number of reasons.. * It seems to be exhibiting kernel bugs (random system freezes for absolutely no reason. Unaccessable via SSH or serial console/ALOM). * We (redbrick) seemed to be the only people anywhere actually using Linux on a production T2000. This worries us greatly, as it means vendors are unlikely to put too much time into fixing bugs. * A number of bits of software were known to be buggy, and we had some of them patched ourselves. (For example, libmysqlclient15off) * Ubuntu 8.04 doesn't support SPARC at all, which kinda ties back into the second point. People aren't interested in supporting it. Debian has a SPARC port that apparently supports a Niagara CPU, but there seems to be nobody (like, absolutely nobody, anywhere) using it in production. I only came across one reference to one guy using it in testing. For a morning's worth of googling, this isn't encouraging. * Gentoo (who seem to have the biggest Niagara uptake of all of the linuxes) makes admins break out in a cold sweat at the very mention of it's name. (I quite like gentoo as it happens, but I'm weird) Anyway, that's why we think Linux is a bad idea (tm). Unfortunately, that leaves us with Solaris as our only real option. One or two of the BSDs support Niagara, but they seem to be even less mature then linux. We've installed it on a test basis, to see how it goes really. We're considering breaking it into multiple LDOMs - logical Solaris domains, which are kinda like Xen virtual machines, only with Sun logos everywhere. See here for more info: http://www.sun.com/bigadmin/hubs/ldoms/ And here for a fancy PDF about them (even has pictures): http://www.sun.com/blueprints/0207/820-0832.pdf An idea is that we'd have a bigish LDOM for logins and apache (because we want users to be able to log into the WWW machine), another for MySQL, another for secondary LDAP, and another for maybe jakarta/tomcat/glassfish/whatever java webapp server we end up using. The LDAP and MySQL ones would obviously be smaller than the Apache and login one. The main benefit of this is security, really. Of course it means remembering 4 more root passwords, but that's a minor issue :) That's all really. Anyone have any feedback? We're completely open to suggestions on this, nothing has been decided with murphy at this point. -Andrew -- RedBrick/Gamessoc/Filmsoc Webmaster 08/09

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[Admin-discuss] DNS Changes
by Eoghan Cotter 26 Jun '08

26 Jun '08

Hi Folks I've moved primary dns (36.206.15.53) to deathray for the time being as cynic is currently down. The very long ssh times this evening were the result of reverse lookups failing we think Since I've gotten bind running on deathray the wait time for the password prompt has come back down to something less noticably, but still, i think, slower than cynic so primary will probably go back there and deathray will become a seconday DNS server. Cheers Eoghan -- Eoghan Cotter Treasurer DCU Surf 'n' Sail Club Secretary DCU Societies and Publications Committee Equipment Officer DCU SPC DCU Networking Society (Redbrick) Education Officer

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[Admin-discuss] Plans, and stuff
by Andrew Harford 26 Jun '08

26 Jun '08

Hi, The four of us met up last night, planned out in a bit more detail where we wanted everything to end up, and what exactly we were going to do next. I then made shiny diagrams of what we planned: http://www.redbrick.dcu.ie/~receive/plan/ It pretty much speaks for itself, our priority is still getting murphy running. Myself and cian are going to re-install murphy while johan and werdz get OpenDS working on cynic. Once we move apache etc. from deathray, we're going to need to re-build it's raid array, which should hopefully sort out the disks being "slow and weird" and then get more primary services back working on deathray. a. -- Andrew Harford System Administrator, DCU Networking Society Ordinary Member, Societies & Publications Committee There's always been a lot of tension between Lois and me, and it's not so much that I want to kill her, it's just, I want her not to be alive anymore. --Stewie Griffin

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[Admin-discuss] Murphy, Apache & redbrick.dcu.ie
by Andrew Harford 13 Jun '08

13 Jun '08

Hey, We had a talk last night, about what we'd like to focus on next, the idea being that the 4 of us would be working towards getting something working properly, rather than just trying to fix stuff. The stuff werdz has done recently has been invaluable, and i hate to think what state the place would be in without him, but none of it has been related to webmaster. All our plans to have cool new web things ready for september have, understandably, been on hold cause of all this. To that end we've decided that the first thing we'd like to tackle together is getting murphy-ldg1 finished so that it can take over apache, and werdz can start working on shiny web projects. I'm going to spend a good chunk of this weekend on it's apache, cian will be looking at firewalling it, and johan's going to get ldap working on it. Colm: I've read all your blog posts about testing apache on murphy, but if there's anything else you think I should know/would be helpful then let me know :) I know this hass been discussed in the past, but i'd like us to get back to having a website at redbrick.dcu.ie, re-writing anything there to www.redbrick, and using jumpgate or something to route any lost ssh connections back to login.redbrick. a. -- Andrew Harford System Administrator, DCU Networking Society Ordinary Member, Societies & Publications Committee What we were after now was the old surprise visit. That was a real kick and good for laughs and lashings of the old ultraviolence. -- Alex (A Clockwork Orange)

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[Admin-discuss] No Downtime Saturday
by Andrew Harford 12 Jun '08

12 Jun '08

Apologies, I meant to send this on here before i put it on boards - we won't be able to work on minerva's raid array this weekend, as there's no way the backups will be done in time. We'd planned to re-install severus on Monday, but it took so long to build a new RAID array that we didn't have time :( Severus was re-installed on Tueday, and the backups are running now, i'd guess it'll take about three days to get the first one complete. a. -- Andrew Harford System Administrator, DCU Networking Society Ordinary Member, Societies & Publications Committee My name is Maximus Decimus Meridius, Commander of the Armies of the North, General of the Felix Legions, loyal servant to the true emperor, Marcus Aurelius. Father to a murdered son, husband to a murdered wife. And I will have my vengeance, in this life or the next. --Maximus (Gladiator)

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[Admin-discuss] Fwd: [rb-admins] Centralised Backups of RedBrick config files
by Andrew Harford 03 Jun '08

03 Jun '08

Hi, When we were re-installing minerva I had this idea about having a centralised location containing all config files, scripts etc. that are duplicated accross multiple machines. I've been copying files manually to /srv/admin/skel as i've been working on them, but that's gotten fairly old, so i've written a small script to keep it synchronised. This script is now running daily on carbon/minerva. We'll probably want to replace this with something fancier that does revision control etc at some stage, but I think this is fine for now. I'm including the script below in case someone spots some mad error i've made ;) a. ---------------------------------------------------------------------- #!/bin/bash # # Script to backup to /srv/admin/skel # Copys newer versions of files from local # machine to backup directory # # Andrew Harford (receive(a)redbrick.dcu.ie) # May 2008 # ############# # Variables # ############# localprefix=/ backupprefix=/srv/admin/skel/ lockfile=lock_backup_in_progress ################# # wait for lock # ################# while [ -f $backupprefix$lockfile ]; do sleep 60 done touch $backupprefix$lockfile ############ # Do stuff # ############ files=$(find /srv/admin/skel -type f -printf "%P\n") for filename in $files; do if [ -f $localprefix$filename ]; then cmp -s $localprefix$filename $backupprefix$filename || (cp -a $localprefix$filename $backupprefix$filename) fi done ######################## # Clear lock, and exit # ######################## rm $backupprefix$lockfile exit 0 -- Andrew Harford System Administrator, DCU Networking Society Ordinary Member, Societies & Publications Committee Son, when you participate in sporting events, it's not whether you win or lose: it's how drunk you get. --Homer Simpson

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