Here is a list of issues (and hopefully resolutions) encountered while getting Linux-HA to run on an OpenPower 720:
- Sharing DASD between two LPARs
Hopefully at this point "Hello shared world!" is displayed on your terminal.
- Shut down all affected LPARs, including Virtual I/O Server
- On HMC, create two virtual SCSI server adapters for Virtual I/O Server LPAR with unique slot numbers (i.e. 31 and 41)
- On HMC, create a virtual SCSI client adapter for each Linux LPAR that connects to the slot numbers from previous step (i.e. VIO.31 on first LPAR, VIO.41 on second)
- Activate Virtual I/O Server LPAR and login
- Assign the same backing DASD to both of the newly created vhosts using different device names; for example (assuming dasdvg volume group exists, shared data is to be 20GB, and vhost5 and vhost6 represent slots 31 and 41, respectively):
- mklv -lv my_shared_data dasdvg 20G mkvdev -vdev my_shared_data -vadapter vhost5 -dev dev_LPAR1_shared mkvdev -vdev my_shared_data -vadapter vhost6 -dev dev_LPAR2_shared
- Activate both Linux LPARs and login
- From first Linux LPAR (assuming shared data will be JFS partition on /dev/sdb):
- From second Linux LPAR (again assuming shared data will be JFS partition on /dev/sdb):
- mkdir /shared_data mount -t jfs /dev/sdb /shared_data blockdev --flushbufs /dev/sdb cat /shared_data/my_file
- HMC and VIOS command complexity
Command line syntax for both the HMC and Virtual I/O Server are extremely complex. See for yourself, here is the 1375-line script used to setup the LPARs on the HMC (LWE-HMCScript.sh) and here is the 300-line script used to setup the LPARs' virtual Ethernet and SCSI adapters on the VIOS (LWE-VIOSScript.sh).