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Posts from 2009

Speeding up Solaris package installation

solarisJun 15, 2009 1 min read

This putback from Casper should make all Solaris admins happy:

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Migrating KVM hosts with virsh

virtualizationJun 15, 2009 1 min

I played around with KVM live migration over the weekend, and it worked flawlessly. When I was first getting the environment (i.e., /etc/libvirt/libvirtd.conf, /etc/sysconfig/libvirt, SASL credentials, etc.) set up to allow migrations to work, I was greeted with the following error: This message wasn't the most descriptive error I've ever read, so I turned to the libvirt source to see what was going on. I saw the following comment: And immediately fired up virsh to double check the migrate syntax I was using: I had accidently run the migrate command from the destination host instead of the source host. Once I knew what was going on, I fired off the migrate from the source host and everything worked flawlessly: virsh # migrate --live kvmnode1 qemu+tcp://thecrue/system virsh # I really dig KVM, and have recently become somewhat smitten with openvz…

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Adding Machine Check Exception Logging support to the Linux kernel

linuxJun 14, 2009 1 min

In my previous post, I mentioned how the mcelog utility can be used to detect hardware problems. Mcelog relies on the /dev/mcelog device being present, which requires the kernel to be built with the following options: To enable these, you can select the following options once you run 'make menuconfig':

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Initng speeds up Linux boot times / provides service resilancy

linuxJun 14, 2009 1 min

One feature I really liked in Solaris 10 was SMF. It provides a framework using services manifests on the system to automatically respawn services should they die off. It handles dependencies, restarts, and a single unified command set to configure the system using svcs, svccfg, and svcadm. Linux looks like they've started to integrate some of these features with a modified Init daemon that not only restarts defined services, but improves boot time…

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Dealing with slow lofs performance on opensolaris hosts

solarisJun 13, 2009 1 min

I went to update the Nevada image on my jumpstart server today, and noticed that my loopback mount was performing terribly: Ouch! 11 reads per second causes the loopback device to become 100% busy. It turns out this is bug 6806627 which is fixed in Nevada build 112. I got around the issue by using a Linux host to copy the CD contents, and then running setup_install_server from that location…

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