You can't. It's now in the pool as a single-drive vdev. vdevs can not be removed from a pool.
That's the bad news.
The worse news is that you've now effectively got a RAID-0 with your
raidz2-0 vdev and the
c2t13d0 vdev. This is NOT good. It's doubleplusungood.
Your options are:
- to live with the pool you have created
- backup, destroy and re-create the pool, and restore.
Neither option is good. backup/recreate/restore is the right option in the long run, but requires significant downtime (the only way to avoid that is to create a SECOND pool of the same size or larger and
zfs send to that).
BTW, one thing can do to fix the lack of redundancy is to attach a mirror to the
c2t13d0 vdev. Maybe use one of the spares if they're the same size.
Use something like:
zpool attach data c2t13d0 anotherdisk
It's far from ideal but a RAIDZ2 vdev striped with a mirror vdev has redundancy (still an abomination but not one that's going to eat your data), while RAIDZ2 striped with a single-drive doesn't have any reliable redundancy (some of your data will be ONLY on the single-drive vdev. This will invariably turn out to be your most valuable and irreplaceable data).
It does make the first option ("live with it") suck a lot less...at least for now. In the long run, you'll want to rebuild your pool.
I don't have access to the Solaris man page, but here's a relevant extract from the ZFS On Linux version of the
zpool man page (bolding added by me for emphasis). Solaris version should be the same or very similar:
zpool attach [-f] [-o property=value] pool device new_device
Attaches new_device to an existing zpool device. The existing device cannot be part of a raidz configuration. If device is not currently part of a mirrored configuration, device automatically transforms into a two-way mirror of device and new_device. If device is part of a two-way mirror, attaching new_device creates a three-way mirror, and so on. In either case, new_device begins to resilver immediately.