Sunday, June 18, 2017

Steps for Moving ASM Disk from FRA to DATA

Due to some unexpected data load, the space in DATA diskgroup became critically low on one of the production systems during middle of night on the weekend. There was no time to get a new disk and we needed the space to make room for new data load scheduled to be run after 3 hours.

Looked at the tablespaces space in DATA diskgroup and there wasn't much hope in terms of moving or shrinking or deleting anything. Also the upcoming data load was direct path load which always writes above the high water mark in segments, so shrinking wasn't of much help.

Looked at the FRA diskgroup and found out that there was plenty of space there, so I decided to rob Peter to pay Paul. The plan was to remove a disk from FRA diskgroup and add it to DATA. This all was done online and these were general steps:

Steps for Moving ASM Disk from FRA to DATA :

1) Remove Disk from FRA diskgroup

SQL> alter diskgroup FRA drop disk FRA_06;

Diskgroup altered.

2) Wait for Rebalance to finish

SQL> SELECT group_number, operation, state, power, est_minutes FROM v$asm_operation;

3) Add disk to the DATA diskgroup

alter diskgroup DATA add disk '/dev/myasm/superdb_fra_06' name DATA_06 rebalance power 8;

4) Wait for Rebalance to finish

SQL> SELECT group_number, operation, state, power, est_minutes FROM v$asm_operation;

This provided a much needed breather for the weekend and data load ran successfully. We will be making sure that we provision more disks to the DATA diskgroup and return the FRA disk to FRA with thanks.


No comments: