Need GUI for offlining a device for removal

[delphij]

Currently there is no GUI way to offline a disk for removal, this makes it impossible to replace disk without CLI.

Roughly replacing a disk needs the following steps:

• 'zpool offline <poolname> <disk>'
• swapoff <swap on the disk>

(At this point, the disk can be pulled away, zfs will let the underlying GEOM device go at this point)

Then, after that, when a new disk is put back, the 'replace' of the offlined disk should do:

• partition on that disk;
• swapon <swap on the disk>
• zpool replace <poolname> <disk>

(and afterwards, zpool detach <poolname> <disk>/old)

Currently the code seems to do the two steps in one step.

[william]

This has been done in volumes branch r8160:8162

[gcooper]

Please leave this open until the code has been properly integrated into trunk. The current code does a poor job at trying to replace drives..

[montjoy1]

Also, make sure this works if you reboot after the disk went offline and add the new disk after the server is booted again. There was no way in the GUI to even see the new disk besides adding a new volume.

[delphij]

Replying to montjoy1:

Also, make sure this works if you reboot after the disk went offline and add the new disk after the server is booted again. There was no way in the GUI to even see the new disk besides adding a new volume.

I don't quite get it -- isn't the whole point of having 'offline' to replace hard drive without bringing the system down?

[gcooper]

The big underlying assumption here is that the controller used for testing must support hotswap. Not all controllers (pre-ICH8, and I'm sure there are more) support hotswap.

[delphij]

Replying to gcooper:

The big underlying assumption here is that the controller used for testing must support hotswap. Not all controllers (pre-ICH8, and I'm sure there are more) support hotswap.

It might be worthy to mention somewhere that 'offline' is only useful for hotswap-capable hardware and make sure that the 'replace' works in cold swapped setup.

[gcooper]

Or "hotswap removal and insertion only works with certain versions of hardware and chipsets". I worked with a company recently that only supported hotswap insertion due to design flaws on the motherboard where it would potentially ground/Vdd bounce and kill off the the drives and/or controller after X number of inserts and removals, even though the chipset supported hotswap.

Hotswap is really more of a server feature than a home feature TBH, as hotswap removal in a chassis without drive sleds and proper power hookup is dangerous anyhow.

[william]

Merge in r8423