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Posts in Storage
Which file system should I use with Gluster?
I was reading through the Gluster 3.2.5 release notes today and came across the following blurb: Red Hat recommends XFS when formatting the disk sub-system. XFS supports metadata journaling, which facilitates quicker crash recovery. The XFS file system can also be de-fragmented and enlarged while mounted and active. Any other POSIX compliant disk file system, such as Ext3, Ext4, ReiserFS may also work, but has not been tested widely…
$ read more →The importance of keeping your storage array firmware up to date
A couple of weeks back I attempted to migrate a pair of clustered Solaris 10 servers to a new disk storage array. After rebooting into single user mode to pick up the new devices, I went to add the new quorum disk with clquorum. This resulted in both nodes panicking with the following panic string: At first I thought I was doing something wrong, but after a lot of research I figured out that there were a couple of Solaris-related bugs in the version of the storage array firmware we were using. One of the bugs was triggering the panic above, and after the array was patched everything worked as expected…
$ read more →Locating Linux LVM (Logical Volume Manager) free space
The Linux Logical Volume Manager (LVM) provides a relatively easy way to combine block devices into a pool of storage that you can allocate storage out of. In LVM terminology, there are three main concepts: Physical Volumes A sequence of sectors on a physical device. Volume Groups A group of physical volumes. Logical Volumes A logical device that is allocated from a volume group…
$ read more →Improved ZFS scrub statistics in Solaris 10 update 9
I talked about the ZFS scrub feature a few months back. In the latest Solaris 10 update the developers added additional scrub statistics, which are quite handy for figuring out throughout and estimated completion times: This sure beats the previous output! Nice job team Solaris.
$ read more →Another interesting finding about gluster replicas
In a previous post I talked about my problems getting gluster to expand the number of replicas in a volume. While experimenting with the gluster utilities "add-brick" option I wanted to see if adding two more bricks would replicate the existing data across four bricks (two old, two new), or if the two new bricks would be a replica pair and the two previous bricks would be a replica pair. To see what would happen I added two more bricks: And then checked out the status of the volume: Interesting. The volume is now a distributed-replicated volume, and has a two by two configuration giving four nodes in total…
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