Reorg Of A RAID/LVM System

I have a system with 4 disk drives, two 512 Gb and two 1 Tb. It look like this:

CentOS release 5.9 (Final)

Disk /dev/sda: 500.1 GB, 500107862016 bytes Disk /dev/sdb: 1000.2 GB, 1000204886016 bytes Disk /dev/sdc: 500.1 GB, 500107862016 bytes Disk /dev/sdd: 1000.2 GB, 1000204886016 bytes
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Disk /dev/sda: 500.1 GB, 500107862016 bytes
16 heads, 63 sectors/track, 969021 cylinders Units = cylinders of 1008 * 512 = 516096 bytes

Device Boot Start End Blocks Id System
/dev/sda1 * 1 1985 1000408+ fd Linux raid autodetect
/dev/sda2 1986 9923 4000752 82 Linux swap / Solaris
/dev/sda3 9924 969021 483385392 fd Linux raid autodetect

Disk /dev/sdb: 1000.2 GB, 1000204886016 bytes
255 heads, 63 sectors/track, 121601 cylinders Units = cylinders of 16065 * 512 = 8225280 bytes

Device Boot Start End Blocks Id System
/dev/sdb1 * 1 125 1004031 fd Linux raid autodetect
/dev/sdb2 126 624 4008217+ 82 Linux swap / Solaris
/dev/sdb3 625 121601 971747752+ fd Linux raid autodetect

Disk /dev/sdc: 500.1 GB, 500107862016 bytes
255 heads, 63 sectors/track, 60801 cylinders Units = cylinders of 16065 * 512 = 8225280 bytes

Device Boot Start End Blocks Id System
/dev/sdc1 * 1 125 1004031 fd Linux raid autodetect
/dev/sdc2 126 4096 31897057+ 82 Linux swap / Solaris
/dev/sdc3 4097 60801 455482912+ fd Linux raid autodetect

Disk /dev/sdd: 1000.2 GB, 1000204886016 bytes
255 heads, 63 sectors/track, 121601 cylinders Units = cylinders of 16065 * 512 = 8225280 bytes

Device Boot Start End Blocks Id System
/dev/sdd1 * 1 125 1004031 fd Linux raid autodetect
/dev/sdd2 126 624 4008217+ 82 Linux swap / Solaris
/dev/sdd3 625 121601 971747752+ fd Linux raid autodetect

The four 1 GB partitions (sd[abcd]1) are configured as a RAID 1 array with a single ext4
filesystem mounted as /boot.

Swap is Swap…

the two smaller drives (sd[ac]3) partitions are configured as a RAID 1 array containing an LVM
physical volume (md1). the two larger drives (sd[bd]3) are configured as a RAID 1 array containing an LVM physical volume (md2).


# pvdisplay
— Physical volume -