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dd problems
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I'll reply in this thread too: What exactly are you trying to accomplish by doing that?
iirc, dd'ing the entire hdisk like that also results in the pvid area being duplicated. pvid's are supposed to be unique, so you might cause ODM confusion.
iirc, dd'ing the entire hdisk like that also results in the pvid area being duplicated. pvid's are supposed to be unique, so you might cause ODM confusion.
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Hi,
If you want to mirror to make then identical, you can use "mirrovg", as you can make identical copies. The only problem that you might have is about your physical partitions size. If the PP size of your 4.5 Gb is 8Mb, you will be unable to add the 9Gb disk to the same VG, and then you will not be able to use mirrorvg. If your PP size is 16Mb or greater there will be no ploblem.
The real problem is a limitation about LVM's maximum number of PP's per PV's (1016). If your AIX box is lower than 4.3.2(I think), then there's a workaround (change the "factor" of the VG, using "chvg -t 2". Note that you will have some free PP's in all PV's of your VG). If you use chvg, the limit of PP's in each PV of the VG will be 2032. When ypou get the two disks in the same VG, you will be able to use mirrorvg ("mirrorvg –c 2 –m –S VGname PVname"
. I must advise you: do not use chvg if you are unsure about what you are doing. After doing this you will be unable to import this VG in AIX 4.3.1 or earlier.
Any questions, please ask
regards,
HTT
If you want to mirror to make then identical, you can use "mirrovg", as you can make identical copies. The only problem that you might have is about your physical partitions size. If the PP size of your 4.5 Gb is 8Mb, you will be unable to add the 9Gb disk to the same VG, and then you will not be able to use mirrorvg. If your PP size is 16Mb or greater there will be no ploblem.
The real problem is a limitation about LVM's maximum number of PP's per PV's (1016). If your AIX box is lower than 4.3.2(I think), then there's a workaround (change the "factor" of the VG, using "chvg -t 2". Note that you will have some free PP's in all PV's of your VG). If you use chvg, the limit of PP's in each PV of the VG will be 2032. When ypou get the two disks in the same VG, you will be able to use mirrorvg ("mirrorvg –c 2 –m –S VGname PVname"
. I must advise you: do not use chvg if you are unsure about what you are doing. After doing this you will be unable to import this VG in AIX 4.3.1 or earlier.Any questions, please ask
regards,
HTT
MoshiachNow
IS-IT--Management
Right.
However,dd also does the job,taking a snap of a good system disk at certain point.
What we do in such a case -we keep the other disk phisically disconnected till the originall one crashes.
Then we connect the other disk back and boot from it.
Only one PVID is active at a time. "Long live king Moshiach !"
h
However,dd also does the job,taking a snap of a good system disk at certain point.
What we do in such a case -we keep the other disk phisically disconnected till the originall one crashes.
Then we connect the other disk back and boot from it.
Only one PVID is active at a time. "Long live king Moshiach !"
h
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