From mboxrd@z Thu Jan 1 00:00:00 1970 From: Willem Verbruggen Subject: Multipath 0.5.0 sets all path priorities to 50 with SCST 3.1.0 ALUA for group_by_prio Date: Sat, 2 Apr 2016 13:19:58 +0200 Message-ID: <56FFAADE.3080405@anagky.be> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii"; Format="flowed" Content-Transfer-Encoding: 7bit Return-path: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: dm-devel-bounces@redhat.com Errors-To: dm-devel-bounces@redhat.com To: christophe.varoqui@opensvc.com, dm-devel@redhat.com List-Id: dm-devel.ids Dear, We were upgrading multipath-tools 0.4.9 to 0.5.0 on a dual node DRBD cluster with SCST 3.1.0 ISCSI exports and three XEN VM nodes. All 5 servers running: root@cenbersto002:/usr/src# uname -a Linux cenbersto002 4.1.18 #1 SMP Sun Mar 27 10:16:46 CEST 2016 x86_64 GNU/Linux For multipath 0.5.0 we cannot get the path priorities to work. Multipath gives all of them the priority 50 no matter what and puts all paths in one active group. Is it a bug in 0.5.0 or did we still make a mistake in our upgraded configuration file (we checked all documentation we could find and did multiple tests)? For 0.4.9 it still works fine on this upgraded platform. Then we get an active group with prio 130 and an enabled failover group with prio 50. Config 0.5.0: root@cenbernod001:~# cat multipath.conf devices { device { vendor "SCST_BIO" # product "*" # hardware_handler "1 alua" # features "3 queue_if_no_path pg_init_retries 50" # path_selector "queue-length 0" } } defaults { polling_interval 10 path_selector "round-robin 0" path_grouping_policy group_by_prio uid_attribute "ID_SERIAL" getuid_callout "/lib/udev/scsi_id --whitelisted --device=/dev/%n" prio alua path_checker directio no_path_retry queue rr_min_io 100 rr_min_io_rq 100 flush_on_last_del no max_fds 8192 rr_weight priorities failback immediate queue_without_daemon no user_friendly_names no mode 644 uid 0 gid disk # hardware_handler "1 alua" } blacklist { devnode "^(ram|raw|loop|fd|md|dm-|sr|scd|st)[0-9]*" devnode "^hd[a-z]" devnode "^sda$" devnode "^sdb$" # wwid 350014ee1aed0e771 # wwid 350014ee158048877 } blacklist_exceptions { # device { # vendor SCST_BIO # } property "(ID_SCSI_VPD|ID_WWN|ID_SERIAL)" devnode "^sd[c-z]+" devnode "^sda[a-z]+" devnode "^sdb[a-z]+" } multipaths { multipath { wwid 26534376437633839 alias cenbererpprd007 } ... For multipath 0.4.9 we get the desired result: cenbererbprd402 (26434373934373262) dm-44 SCST_BIO,cenbererbprd402 size=20G features='1 queue_if_no_path' hwhandler='0' wp=rw |-+- policy='round-robin 0' prio=130 status=active | |- 92:0:0:0 sdce 69:32 active ready running | |- 93:0:0:0 sdcf 69:48 active ready running | |- 150:0:0:0 sdek 128:192 active ready running | `- 198:0:0:0 sdgg 131:192 active ready running `-+- policy='round-robin 0' prio=50 status=enabled |- 106:0:0:0 sdcs 70:0 active ready running |- 107:0:0:0 sdct 70:16 active ready running |- 157:0:0:0 sder 129:48 active ready running `- 251:0:0:0 sdig 135:0 active ready running Config 0.4.9: root@cenbernod003:~# cat /etc/multipath.conf devices { device { vendor "SCST_BIO" # product "VIRTUAL-DISK" } } ## ## This is a template multipath-tools configuration file ## Uncomment the lines relevent to your environment ## defaults { udev_dir /dev polling_interval 10 selector "round-robin 0" path_grouping_policy group_by_prio getuid_callout "/lib/udev/scsi_id --whitelisted --device=/dev/%n" prio alua path_checker directio rr_min_io 100 flush_on_last_del no max_fds 8192 rr_weight priorities failback immediate no_path_retry queue queue_without_daemon no user_friendly_names no mode 644 uid 0 gid disk } blacklist { devnode "^(ram|raw|loop|fd|md|dm-|sr|scd|st)[0-9]*" devnode "^hd[a-z]" devnode "^sda$" devnode "^sdb$" } multipaths { multipath { wwid 26534376437633839 alias cenbererpprd007 } ... In SCST we have ALUA groups with preference to one of the two DRBD nodes for each target: DEVICE_GROUP cenbererbprd402 { DEVICE cenbererbprd402 TARGET_GROUP cenbererbprd402 { group_id 13 preferred 1 state active TARGET cenbersto001:cenbererbprd402 } } Thanks a lot in advance. Kind Regards, Willem -- Willem Verbruggen ANAGKY BVBA Zaakvoerder Thaliastraat 71 +32 (0)497 54 96 36 2600 Antwerpen willem.verbruggen@anagky.be BE 0894.681.775