Gilles Schipper replies
You should use VOLUTIL's suspendmirrvol command. After you've replaced the drive, you simply::volutil
replacemirrvol IT_UV:member2 (plus volume number)
There’s really no need to perform a store-to-disk or buldjob stuff. But if really want to do that, there are a few steps that are needed.
:store command.pub.sys;directory;onvs=mpexl_system_volume_set,diskdump,it_uv,a_uv,b_uv;*t;showThen, store the files on it_uv, ..
Then, after vsclosing, etc,
Then restore of files on that volset -- with the ;olddate;create;keep;partdb options. But I don't think any subsequent steps (vsclose, scratch, then rebuilding the volume set) will be necessary.
What's more, you really should not need to do a FORMATVOL. I've only once actually ever needed to do that -- and I did not do it with MPE, which is extremely slow.
A simple VOLUTIL replacemirrvol should do the trick after you've replaced the drive. The fact that the drive is in an "UNKNOWN" state is perfectly normal for the situation you described.