how to create persistent names in a multipath configuration?
situation: two HP Proliant server, each with SLES11SP4. Each has a FC HBA, connected to a HP FC SAN. Each FC HBA has two channels.
I read man 5 multipath.conf. The problem is: i don't have a file multipath.conf. Is this normal ? Do i have to create one ? Where ?
The volume from the SAN appears in each host as two disks: /dev/sd[a-c]. How can i create/obtain persistent names for the volume ? So they don't change when adding/removing a disk.
I have links in /dev/disk/by-path/ which points to the disks. E.g. pci-0000:0d:00.0-fc-0x247000c0ff128f6e-lun-0 -> ../../sdb. Are these persistent ?
Also i'd like to have peristent names for the devices created by the device-mapper.
sunhb65278:~ # multipathd -k
multipathd> list paths
hcil dev dev_t pri dm_st chk_st dev_st next_check
7:0:0:0 sdb 8:16 10 active ready running XXXXXXXXXX 20/20
8:0:0:0 sdc 8:32 50 active ready running XXXXX..... 11/20
multipathd> list maps
name sysfs uuid
3600c0ff00012824b04af7a5201000000 dm-4 3600c0ff00012824b04af7a5201000000
multipathd> list topology
3600c0ff00012824b04af7a5201000000 dm-4 HP,P2000 G3 FC
size=1007G features='1 queue_if_no_path' hwhandler='0' wp=rw
|-+- policy='service-time 0' prio=50 status=active
| `- 8:0:0:0 sdc 8:32 active ready running
`-+- policy='service-time 0' prio=10 status=enabled
`- 7:0:0:0 sdb 8:16 active ready running
I have symlinks in /dev/disk/by-id pointing to dm-4:
lrwxrwxrwx 1 root root 10 Jun 8 20:39 dm-name-3600c0ff00012824b04af7a5201000000 -> ../../dm-4
Are these links persistent ? Or do i have to provide something magic in /etc/udev/rules.d/70-kpartx.rules ?