Greetings all, I'm about to install some new disc drives and replace some old ones on our HP957 system, and wonder if anyone has any tips on avoiding disaster. I've already run SYSGEN and added paths and devices for the new spindles and modified the device id of the ones to be replaced. We are using disc mirroring and the requirement is to: Add a pair of spindles to one volume (merely expand the private volume by one spindle), so I guess I just do something like newmirrvol med1:member4 (44,54) On another mirrored private volume, I need to replace MEMBER1 and MEMBER2 and add a MEMBER4. Naturally, I'm prepared to reload this volume (run BULDACCT to recreate the accounting structure, restore the data, then reset the UDCs). I'd very much like urgent advice on what's going to happen when the system comes up with replaced members on the second volume. Naturally, I'll have to repeat the above command to add the MEMBER4, but what do I do about the replaced members? Any clues? Ron Burnett [log in to unmask]