# cat /etc/redhat-release CentOS Linux release 7.1.1503 (Core) # uname -r 3.10.0-123.20.1.el7.x86_64
Hi,
We use iSCSI over a 10G Ethernet Adapter and SRP over an Infiniband adapter to provide multipathing to our storage:
# lspci | grep 10-Gigabit 81:00.0 Ethernet controller: Intel Corporation 82599ES 10-Gigabit SFI/SFP+ Network Connection (rev 01) 81:00.1 Ethernet controller: Intel Corporation 82599ES 10-Gigabit SFI/SFP+ Network Connection (rev 01) # lspci | grep Mellanox 06:00.0 InfiniBand: Mellanox Technologies MT26428 [ConnectX VPI PCIe 2.0 5GT/s - IB QDR / 10GigE] (rev b0)
Originally the HBAs came up as host0, host1 and host2. After recent reboots we get host1, host2 and host3:
# ls -l /sys/class/scsi_host/host* lrwxrwxrwx. 1 root root 0 Apr 9 19:10 /sys/class/scsi_host/host1 -> ../../devices/platform/host1/scsi_host/host1 lrwxrwxrwx. 1 root root 0 Apr 9 08:12 /sys/class/scsi_host/host2 -> ../../devices/pci0000:00/0000:00:03.2/0000:06:00.0/host2/scsi_host/host2 lrwxrwxrwx. 1 root root 0 Apr 9 08:12 /sys/class/scsi_host/host3 -> ../../devices/pci0000:00/0000:00:03.2/0000:06:00.0/host3/scsi_host/host3
I've observed that at different times during configuration of this host we have had varying combinations of the mapping of HBA to an enumerated /sys node. e.g.:
host0 host2 host3
or
host1 host3 host4
other combinations, etc.
This messes up our multipath filtering for weightedpath priority settings. From /etc/multipath.conf:
defaults { user_friendly_names no find_multipaths yes prio weightedpath prio_args "hbtl 0:.:.:.* 1 [1-9]:.:.:.* 10" path_grouping_policy group_by_prio path_selector "service-time 0" failback immediate polling_interval 5 no_path_retry 12 }
The setting for prio_args fails to set the correct path map topology and priority against an HBA as I can't predict what HBA is what. Consistently iSCSI claims the lowest number but I can't say if that's going to be 0 or 1 a this stage.
Does anyone know how to configure HBAs to stay on a fixed enumeration at boot?
Kind regards, Tom
Tom Robinson IT Manager/System Administrator
MoTeC Pty Ltd
121 Merrindale Drive Croydon South 3136 Victoria Australia
T: +61 3 9761 5050 F: +61 3 9761 5051 E: tom.robinson@motec.com.au