SF windows mirror volume creation

[Anbu]

On Windows  5.0 MP3 I am seeing this behaviour.

I have created a volume v1 with mirror,log type.  It creates 3 plexes for volume v1.
My understanding is that it should create only 2 plexes.

If I don't give the log flag means it creates only volume dest with 2 plexes.

Is it a bug ?


C:\Temp>vxassist -g destdg make v1 100M type=mirror,log
Created a mirrored volume \Device\HarddiskDmVolumes\destdg\v1

C:\Temp>vxprint

Diskgroup = BasicGroup
TY NAME ASSOC KSTATE LENGTH PLOFFS STATE TUTIL0 PUTIL0

Diskgroup = destdg
TY NAME ASSOC KSTATE LENGTH PLOFFS STATE TUTIL0 PUTIL0
dm Harddisk33 destdg1 - 4192902 - - - -
dm Harddisk34 destdg2 - 4192902 - - - -
dm Harddisk35 destdg3 - 4192902 - - - -
dm Harddisk36 destdg4 - 4192902 - - - -
dm Harddisk37 destdg5 - 4192902 - - - -
dm Harddisk38 destdg6 - 4192902 - - - -
dm Harddisk39 destdg7 - 4192902 - - - -
dm Harddisk40 destdg8 - 4192902 - - - -
v dest - ENABLED 204800 - ACTIVE - -
pl dest-01 dest ENABLED 204800 - ACTIVE - -
pl dest-02 dest ENABLED 204800 - ACTIVE - -
dg destdg destdg - - - - - -
sd destdg1-01 dest-01 ENABLED 204800 0 - - -
sd destdg1-02 v1-03 ENABLED 2 0 - - -
sd destdg2-01 dest-02 ENABLED 204800 0 - - -
sd destdg3-01 v1-01 ENABLED 204800 0 - - -
sd destdg4-01 v1-02 ENABLED 204800 0 - - -
v v1 - ENABLED 204800 - ACTIVE - -
pl v1-01 v1 ENABLED 204800 - ACTIVE - -
pl v1-02 v1 ENABLED 204800 - ACTIVE - -
pl v1-03 v1 ENABLED 204800 - ACTIVE - -

Diskgroup = srcdg

 

[Jay_Kim]

When you create a mirror+log, it creates 3 plexes.
1 for each side of mirror and 1 DRL (dirty region log)
So that is the correct outcome for such command.
btw, I'm assuming this is SFW 5.0 MP2 (not MP3)
But regardless of version, result would be same. =)

Below command will give you a complete picture as to the volume structure and its plexes:

vxvol -g destdg volinfo v1

You can also check the destdg diskgroup from the VEA gui and check the diskview tab to see which subdisk lies in which harddisk.
Or select the volume v1 from VEA left tree pane and check the mirrors and the subdisks tab for more info on how the volume is created.