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HA-iSCSI

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Royal and Fiordland are the lab's storage servers.

Hardware

Royal and Fiordland each have 2 QLA2200 HBAs in them. Each server has a single path to each Fibre Channel Switch (Powervault 51F). Each switch then has a connection to one of the 224Fs controllers. This provides two completely separate Fibre Channel fabrics from the hard drive itself to the server. Any switch, IO module, or HBA can explode and HA-iSCSI will still be up.

Currently, 3 Dell 224F JBODs are being used. The 660Fs with their smart controllers were giving problems: trying to reset the 224Fs, not liking to be configured and such. Thumbtack and Soupspoon have 14x73GB drives and Bigfish has 14x146GB drives.

Software

Currently, the "iSCSI Enterprise Target" is used (http://iscsitarget.sourceforge.net/). This is the iscsitarget package in portage and is also known as iet. IETD provides two IO methods for targets, BlockIO and FileIO. FileIO uses the Linux page cache (filesystem cache) allowing reads to be cached, but everything must be copied twice. BlockIO does not use the page cache and thus does not have to copy data twice, resulting in faster write speeds, but slightly reduced read speeds. Since VMs can cache reads, but not writes, it was decided to go for faster write speeds and use BlockIO.

In addition to HA-iSCSI, the storage servers provide imageserver (not yet HA) and HA-NFS used for /usr/portage on vms and vm configs and locks.