[ClusterLabs] questions about fence_scsi

[Andrei Borzenkov]

On Fri, Jun 15, 2018 at 10:14 AM, Stefan Krueger <Shadow_7 at gmx.net> wrote:
> Hello,
>
> so far as I understand I can use fence_scsi on a two node cluster, if the fence running on one cluster the other cluster has no access to this devices, correct?

If I parse this sentence correctly - no, that's not correct to my best
knowledge. All active nodes have access to shared resource - only when
node fails will it be fenced (i.e. access to devices revoked), and
unfenced again (i.e. access granted) when node comes back.

> I've a 2node cluster with shared JBODs and configure fence_scsi, but I still can use/mount all this devices on both nodes. Did I something wrong?
> My Config:
>
> pcs resource
>  Resource Group: zfs-storage
>      vm_storage (ocf::heartbeat:ZFS):   Started zfs-serv3
>      ha-ip      (ocf::heartbeat:IPaddr2):       Started zfs-serv3
> root at zfs-serv4:~# pcs config
> Cluster Name: zfs-vmstorage
> Corosync Nodes:
>  zfs-serv3 zfs-serv4
> Pacemaker Nodes:
>  zfs-serv3 zfs-serv4
>
> Resources:
>  Group: zfs-storage
>   Resource: vm_storage (class=ocf provider=heartbeat type=ZFS)
>    Attributes: pool=vm_storage importargs="-d /dev/disk/by-vdev/"
>    Operations: monitor interval=5s timeout=30s (vm_storage-monitor-interval-5s)
>                start interval=0s timeout=90 (vm_storage-start-interval-0s)
>                stop interval=0s timeout=90 (vm_storage-stop-interval-0s)
>   Resource: ha-ip (class=ocf provider=heartbeat type=IPaddr2)
>    Attributes: ip=172.16.101.73 cidr_netmask=16
>    Operations: start interval=0s timeout=20s (ha-ip-start-interval-0s)
>                stop interval=0s timeout=20s (ha-ip-stop-interval-0s)
>                monitor interval=10s timeout=20s (ha-ip-monitor-interval-10s)
>
> Stonith Devices:
>  Resource: fence-vm_storage (class=stonith type=fence_scsi)
>   Attributes: pcmk_monitor_action=metadata pcmk_host_list=172.16.101.74,172.16.101.75 devices=" /dev/disk/by-vdev/j3d03-hdd /dev/disk/by-vdev/j4d03-hdd /dev/disk/by-vdev/j3d04-hdd /dev/disk/by-vdev/j4d04-hdd /dev/disk/by-vdev/j3d05-hdd /dev/disk/by-vdev/j4d05-hdd /dev/disk/by-vdev/j3d06-hdd /dev/disk/by-vdev/j4d06-hdd /dev/disk/by-vdev/j3d07-hdd /dev/disk/by-vdev/j4d07-hdd /dev/disk/by-vdev/j3d08-hdd /dev/disk/by-vdev/j4d08-hdd /dev/disk/by-vdev/j3d09-hdd /dev/disk/by-vdev/j4d09-hdd /dev/disk/by-vdev/j3d10-hdd /dev/disk/by-vdev/j4d10-hdd /dev/disk/by-vdev/j3d11-hdd /dev/disk/by-vdev/j4d11-hdd /dev/disk/by-vdev/j3d12-hdd /dev/disk/by-vdev/j4d12-hdd /dev/disk/by-vdev/j3d13-hdd /dev/disk/by-vdev/j4d13-hdd /dev/disk/by-vdev/j3d14-hdd /dev/disk/by-vdev/j4d14-hdd /dev/disk/by-vdev/j3d15-hdd /dev/disk/by-vdev/j4d15-hdd /dev/disk/by-vdev/j3d16-hdd /dev/disk/by-vdev/j4d16-hdd /dev/disk/by-vdev/j3d17-hdd /dev/disk/by-vdev/j4d17-hdd /dev/disk/by-vdev/j3d18-hdd /dev/disk/by-vdev/j4d18-hdd /dev/d
>  isk/by-vdev/j3d19-hdd /dev/disk/by-vdev/j4d19-hdd log /dev/disk/by-vdev/j3d00-ssd /dev/disk/by-vdev/j4d00-ssd cache /dev/disk/by-vdev/j3d02-ssd"
>   Meta Attrs: provides=unfencing
>   Operations: monitor interval=60s (fence-vm_storage-monitor-interval-60s)
> Fencing Levels:
>
> Location Constraints:
> Ordering Constraints:
> Colocation Constraints:
> Ticket Constraints:
>
> Alerts:
>  No alerts defined
>
> Resources Defaults:
>  resource-stickiness: 100
> Operations Defaults:
>  No defaults set
>
> Cluster Properties:
>  cluster-infrastructure: corosync
>  cluster-name: zfs-vmstorage
>  dc-version: 1.1.16-94ff4df
>  have-watchdog: false
>  last-lrm-refresh: 1528814481
>  no-quorum-policy: ignore
>
> Quorum:
>   Options:
>
>
> Thanks for help!
> Best regards
> Stefan
> _______________________________________________
> Users mailing list: Users at clusterlabs.org
> https://lists.clusterlabs.org/mailman/listinfo/users
>
> Project Home: http://www.clusterlabs.org
> Getting started: http://www.clusterlabs.org/doc/Cluster_from_Scratch.pdf
> Bugs: http://bugs.clusterlabs.org