Failed to run " vgchange -a s" when vg with lv mirrored And why?

[timber]

As the subject,when i bring my RAC MC to QPK patch in 0706 ver,then i find that i can not active the vg in share mode!? Why ?? Specialy the lv in this VG be mirrored.the error shown as:
# vgchange -a s vgtest
vgchange: Couldn't activate volume group "vgtest":
Bad file number

[Duncan Edmonstone]

It's not a descriptive error message, but the probable cause is that you have mirror write cache enabled for that LV, and that's not allowed in a shared LV. I believe a more descriptive error message is provided in more recent patches (which version of the OS are you on?)

Try the following to sort this out:

vgchange -c n vgtest
lvchange -M n -c y /dev/vgtest/lvolXX # for every lvol that is mirrored

vgchange -a n vgtest
vgchange -a s vgtest

HTH

Duncan

[timber]

Yesï¼ When i set MWC=0 ,the vg can be active in share mode but it need a long time! And seems that the vg is syncing data! I want to know the reasone why vgchange cost so long time and is there any risk about data losing ? Thx