Configuration Automation & Centralized Management With Puppet on Ubuntu from HowtoForge.
Puppet seems easier to setup the cfengine, hopefully it will be as easy to use. Using puppet to push up apt-get updates seems like a worthy task. Hopefully someone puts together a howto on the best practice for that.
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Discussion on the pros and cons of raid-z vs mirroring: WHEN TO (AND NOT TO) USE RAID-Z from Bizarre ! Vous avez dit Bizarre.
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Useful zfs guide: ZFS Best Practices Guide.
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I just installed Nexenta and I’ve been playing around with zfs. I must say the basic replication system is very cool. Seems to work for zvols as well. Remotely replicated iscsi volumes and nfs data sets, is going to make my backups trivial.
root@hzsilo:/tank/test# ls -l /tank/test2/
total 104
-rw-r--r-- 1 root root 104000 Feb 24 00:54 random
-rw-r--r-- 1 root root 104857600 Feb 24 01:00 random2root@hzsilo:/tank/test# rm random2
root@hzsilo:/tank/test# zfs snapshot tank/test@10:00pmroot@hzsilo:/tank/test# zfs send -i tank/test@9:59pm tank/test@10:00pm | zfs receive tank/test2@10:00pm
cannot receive: destination has been modified since most recent snapshotroot@hzsilo:/tank/test# zfs rollback -r tank/test2@9:59pm
root@hzsilo:/tank/test# zfs send -i tank/test@9:59pm tank/test@10:00pm | zfs receive tank/test2@10:00pm
root@hzsilo:/tank/test# ls -l /tank/test2/
total 103
-rw-r–r– 1 root root 104000 Feb 24 00:54 random
For those of you who might have missed it, the send receive pipe could have a ‘ssh -C’ part as well. Brilliant. Plus because of the snapshots the deleted data is still there. The whole rollback thing is probably because of atime from the ls.
Some other stats from Wikipedia:
With that many snapshots possible you could almost have continue data protection. Even with 100 objects to snapshot at one per mintue; 144,000 snapshots, per day, it will be a long time before any limits are reached.
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VMWare bases the MAC address of interface on it’s internal UUID. If you shift a machine (copy, rename) vmware asks to update the UUID. You might get something like this:
# ifup eth0
SIOCSIFADDR: No such device
eth0: ERROR while getting interface flags: No such device
SIOCSIFADDR: No such device
SIOCSIFADDR: No such device
eth0: ERROR while getting interface flags: No such device
eth0: ERROR while getting interface flags: No such device
The solution found by hbraga is to check /etc/iftab. Ubuntu on install adds the MAC address for each interface to this file. Either comment out the lines or update them to reflect the correct details.
Technorati Tags: vmware, ubuntu, network error fix
Just discovered Splunk from Ben Rockwood. Splunk is a cool looking web-based log analysis system, which uses Ajax. I’ve been meaning to do a search and find a good centralised syslog system with a web interface. Seems like I don’t need to go any further.
Check out the tour for more details on how it works.
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The 3.5 version of the IFolder Server has just been released as open source. Yah!
I’ve been wanted to running this for a while as it seems like a well tested system that works well with offline files and is cross-platform. There are even build instruction for Dapper, plus config details. Hopefully I’ll get a chance to test this some time in the next month or so.
Update: Notes on builder IFolder Server on X68_64. Unfortunately it looks a little tricky. Seems I’ll have to figure running a 32bit userland on a 64bit xen kernel. I think they might be some problems with 64bit modules and 32bit modutils, have to check in the mailing list. Also see this review with some good comments.
Here is a xargs shell tip for moving several subversion controlled files.
find . -name \*.html | xargs -n1 -I '{}' svn mv {} ../archive/
Technorati Tags: subversion, shell
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These guys have an interesting looking project called Enomalism Virtualized Management Console which is an open source web based Xen domain management console. After looking at the screen shots, I’m looking forward to seeing how it functions. They have some futher work which seems to leverage this to provide an integrated collaborative content management for business called TYfresco. Combining Zimbra, Sugarcrm and, a new project for me, Alfresco.
I tried to get Zimbra running recently on an Amd64 Debian domU, but ran into 64bit issues. After several attempts at compiling Zimbra, I figure my next try will be with a 32bit chroot.
Anyway I’ve also been thinking along these lines and better Xen management recently. I’ve been considering building my own system based on Cfengine and Layed Subversion. Cfengine is meant to be very powerful, and is some thing I’d like to spend time learning regardless. Laysvn seems easier to use now, however I’m in two minds about its functionality. The balance been easy of use and security is something I have to explore further.
I see a tool like this as being useful for both deploying new and migrating old servers, plus the restoration management in the event of a system failure. However this needs to be balanced against the leakage of system security information from files like /etc/shadow. On one hand it’s important to store this, on the other with a bad implementation it increases the risk that secure information will leaked. Another thing to consider, as indicated by several comments on Tracking, auditing and managing your server configuration with Subversion in 10 minutes, is permissions management.
Finally I saw this cool looking admin tool on freshmeat in my rss reader Great News today. Network wide updates for systems which use APT, or nwu. Maybe this is something I figured I could do with cfengine, or maybe it’s something that can be combined with cfengine. However, very useful work.
As more systems are run on Xen, making it much easier for sysadmins to partition their services on the same hardware and therefore make system maintenance easier on the application. Better tools will have to be produce to assist management on the OS level.
Technorati Tags: xen, etc, management, cfengine, laysvn