# vxdg -fC import mydg
VxVM vxconfigd WARNING V-5-1-554 Disk emc6_199c names group mydg, but group ID differs
VxVM vxconfigd WARNING V-5-1-554 Disk emc6_4175 names group mydg, but group ID differs
VxVM vxconfigd WARNING V-5-1-554 Disk emc6_4171 names group mydg, but group ID differs
VxVM vxconfigd WARNING V-5-1-554 Disk emc6_401f names group mydg, but group ID differs
VxVM vxconfigd WARNING V-5-1-554 Disk emc6_22ab names group mydg, but group ID differs
VxVM vxconfigd WARNING V-5-1-554 Disk emc6_1998 names group mydg, but group ID differs
VxVM vxconfigd WARNING V-5-1-554 Disk emc6_4021 names group mydg, but group ID differs

Looking at the disks, we see that the disk that the DG imported have a different dgid compared to all the other disks:

# vxdisk list emc6_1c88
Device:    emc6_1c88
devicetag: emc6_1c88
type:      auto
hostid:    server102
disk:      name=EMC3_125 id=1217057218.607.server101
group:     name=mydg id=1217057319.609.server101

# vxdisk list emc6_22ab
Device:    emc6_22ab
devicetag: emc6_22ab
type:      auto
hostid:    server102
disk:      name= id=1218021099.632.server102
group:     name=mydg id=1149511351.1278.server101

Reason: A diskgroup with the same name mydg, had been created while the original dg was in a deported state.

Solution

1. Import the original dg with the dgid from one of the disks:
 

# vxdg -fC import 1149511351.1278.server101
 

2. Import the original disk group, providing a new name and also using its dgid:

# vxdg -n mynewdg import 1217057319.609.server101

# vxdisk -o alldgs list | grep mydg
emc6_1c88    auto:cdsdisk   disk01         mynewdg    online
emc6_22ab    auto:cdsdisk   mydg01         mydg       online
emc6_199c    auto:cdsdisk   mydg01         mydg       online
emc6_401f    auto:cdsdisk   mydg01         mydg       online
emc6_1998    auto:cdsdisk   mydg01         mydg       online
emc6_4021    auto:cdsdisk   mydg01         mydg       online
emc6_4171    auto:cdsdisk   mydg01         mydg       online
emc6_4175    auto:cdsdisk   mydg01         mydg       online