[ClusterLabs] DRBD + VDO HowTo?
Eric Robinson
eric.robinson at psmnv.com
Mon May 17 14:37:05 EDT 2021
Andrei --
To follow up, here is the Pacemaker config. Let's not talk about fencing or quorum right now. I want to focus on the vdo issue at hand.
[root at ha09a ~]# pcs config
Cluster Name: ha09ab
Corosync Nodes:
ha09a ha09b
Pacemaker Nodes:
ha09a ha09b
Resources:
Clone: p_drbd0-clone
Meta Attrs: clone-max=2 clone-node-max=1 notify=true promotable=true promoted-max=1 promoted-node-max=1
Resource: p_drbd0 (class=ocf provider=linbit type=drbd)
Attributes: drbd_resource=ha01_mysql
Operations: demote interval=0s timeout=90 (p_drbd0-demote-interval-0s)
monitor interval=60s (p_drbd0-monitor-interval-60s)
notify interval=0s timeout=90 (p_drbd0-notify-interval-0s)
promote interval=0s timeout=90 (p_drbd0-promote-interval-0s)
reload interval=0s timeout=30 (p_drbd0-reload-interval-0s)
start interval=0s timeout=240 (p_drbd0-start-interval-0s)
stop interval=0s timeout=100 (p_drbd0-stop-interval-0s)
Clone: p_drbd1-clone
Meta Attrs: clone-max=2 clone-node-max=1 notify=true promotable=true promoted-max=1 promoted-node-max=1
Resource: p_drbd1 (class=ocf provider=linbit type=drbd)
Attributes: drbd_resource=ha02_mysql
Operations: demote interval=0s timeout=90 (p_drbd1-demote-interval-0s)
monitor interval=60s (p_drbd1-monitor-interval-60s)
notify interval=0s timeout=90 (p_drbd1-notify-interval-0s)
promote interval=0s timeout=90 (p_drbd1-promote-interval-0s)
reload interval=0s timeout=30 (p_drbd1-reload-interval-0s)
start interval=0s timeout=240 (p_drbd1-start-interval-0s)
stop interval=0s timeout=100 (p_drbd1-stop-interval-0s)
Resource: p_vdo0 (class=lsb type=vdo0)
Operations: force-reload interval=0s timeout=15 (p_vdo0-force-reload-interval-0s)
monitor interval=15 timeout=15 (p_vdo0-monitor-interval-15)
restart interval=0s timeout=15 (p_vdo0-restart-interval-0s)
start interval=0s timeout=15 (p_vdo0-start-interval-0s)
stop interval=0s timeout=15 (p_vdo0-stop-interval-0s)
Resource: p_vdo1 (class=lsb type=vdo1)
Operations: force-reload interval=0s timeout=15 (p_vdo1-force-reload-interval-0s)
monitor interval=15 timeout=15 (p_vdo1-monitor-interval-15)
restart interval=0s timeout=15 (p_vdo1-restart-interval-0s)
start interval=0s timeout=15 (p_vdo1-start-interval-0s)
stop interval=0s timeout=15 (p_vdo1-stop-interval-0s)
Stonith Devices:
Fencing Levels:
Location Constraints:
Ordering Constraints:
promote p_drbd0-clone then start p_vdo0 (kind:Mandatory) (id:order-p_drbd0-clone-p_vdo0-mandatory)
promote p_drbd1-clone then start p_vdo1 (kind:Mandatory) (id:order-p_drbd1-clone-p_vdo1-mandatory)
Colocation Constraints:
p_vdo0 with p_drbd0-clone (score:INFINITY) (id:colocation-p_vdo0-p_drbd0-clone-INFINITY)
p_vdo1 with p_drbd1-clone (score:INFINITY) (id:colocation-p_vdo1-p_drbd1-clone-INFINITY)
Ticket Constraints:
Alerts:
No alerts defined
Resources Defaults:
Meta Attrs: rsc_defaults-meta_attributes
resource-stickiness=100
Operations Defaults:
Meta Attrs: op_defaults-meta_attributes
timeout=30s
Cluster Properties:
cluster-infrastructure: corosync
cluster-name: ha09ab
dc-version: 2.0.4-6.el8_3.2-2deceaa3ae
have-watchdog: false
last-lrm-refresh: 1621198059
maintenance-mode: false
no-quorum-policy: ignore
stonith-enabled: false
Tags:
No tags defined
Quorum:
Options:
Here is the cluster status. Right now, node ha09a is primary for both drbd disks.
[root at ha09a ~]# pcs status
Cluster name: ha09ab
Cluster Summary:
* Stack: corosync
* Current DC: ha09a (version 2.0.4-6.el8_3.2-2deceaa3ae) - partition with quorum
* Last updated: Mon May 17 11:35:34 2021
* Last change: Mon May 17 11:34:24 2021 by hacluster via crmd on ha09a
* 2 nodes configured
* 6 resource instances configured (2 BLOCKED from further action due to failure)
Node List:
* Online: [ ha09a ha09b ]
Full List of Resources:
* Clone Set: p_drbd0-clone [p_drbd0] (promotable):
* Masters: [ ha09a ]
* Slaves: [ ha09b ]
* Clone Set: p_drbd1-clone [p_drbd1] (promotable):
* Masters: [ ha09a ]
* Slaves: [ ha09b ]
* p_vdo0 (lsb:vdo0): FAILED ha09a (blocked)
* p_vdo1 (lsb:vdo1): FAILED ha09a (blocked)
Failed Resource Actions:
* p_vdo1_stop_0 on ha09a 'error' (1): call=21, status='Timed Out', exitreason='', last-rc-change='2021-05-17 11:29:09 -07:00', queued=0ms, exec=15001ms
* p_vdo0_stop_0 on ha09a 'error' (1): call=27, status='Timed Out', exitreason='', last-rc-change='2021-05-17 11:34:26 -07:00', queued=0ms, exec=15001ms
* p_vdo1_monitor_0 on ha09b 'error' (1): call=21, status='complete', exitreason='', last-rc-change='2021-05-17 11:29:08 -07:00', queued=0ms, exec=217ms
* p_vdo0_monitor_0 on ha09b 'error' (1): call=28, status='complete', exitreason='', last-rc-change='2021-05-17 11:34:25 -07:00', queued=0ms, exec=182ms
Daemon Status:
corosync: active/disabled
pacemaker: active/disabled
pcsd: active/enabled
The vdo devices are available...
[root at ha09a ~]# vdo list
vdo0
vdo1
> -----Original Message-----
> From: Users <users-bounces at clusterlabs.org> On Behalf Of Eric Robinson
> Sent: Monday, May 17, 2021 1:28 PM
> To: Cluster Labs - All topics related to open-source clustering welcomed
> <users at clusterlabs.org>
> Subject: Re: [ClusterLabs] DRBD + VDO HowTo?
>
> Andrei --
>
> Sorry for the novels. Sometimes it is hard to tell whether people want all the
> configs, logs, and scripts first, or if they want a description of the problem
> and what one is trying to accomplish first. I'll send whatever you want. I am
> very eager to get to the bottom of this.
>
> I'll start with my custom LSB RA. I can send the Pacemaker config a bit later.
>
> [root at ha09a init.d]# ll|grep vdo
> lrwxrwxrwx. 1 root root 9 May 16 10:28 vdo0 -> vdo_multi
> lrwxrwxrwx. 1 root root 9 May 16 10:28 vdo1 -> vdo_multi
> -rwx------. 1 root root 3623 May 16 13:21 vdo_multi
>
> [root at ha09a init.d]# cat vdo_multi
> #!/bin/bash
>
> #--custom script for managing vdo volumes
>
> #--functions
> function isActivated() {
> R=$(/usr/bin/vdo status -n $VOL 2>&1)
> if [ $? -ne 0 ]; then
> #--error occurred checking vdo status
> echo "$VOL: an error occurred checking activation status on
> $MY_HOSTNAME"
> return 1
> fi
> R=$(/usr/bin/vdo status -n $VOL|grep Activate|awk '{$1=$1};1'|cut -d" "
> -f2)
> echo "$R"
> return 0
> }
>
> function isOnline() {
> R=$(/usr/bin/vdo status -n $VOL 2>&1)
> if [ $? -ne 0 ]; then
> #--error occurred checking vdo status
> echo "$VOL: an error occurred checking activation status on
> $MY_HOSTNAME"
> return 1
> fi
> R=$(/usr/bin/vdo status -n $VOL|grep "Index status"|awk
> '{$1=$1};1'|cut -d" " -f3)
> echo "$R"
> return 0
> }
>
> #--vars
> MY_HOSTNAME=$(hostname -s)
>
> #--get the volume name
> VOL=$(basename $0)
>
> #--get the action
> ACTION=$1
>
> #--take the requested action
> case $ACTION in
>
> start)
>
> #--check current status
> R=$(isOnline "$VOL")
> if [ $? -ne 0 ]; then
> echo "error occurred checking $VOL status on $MY_HOSTNAME"
> exit 0
> fi
> if [ "$R" == "online" ]; then
> echo "running on $MY_HOSTNAME"
> exit 0 #--lsb: success
> fi
>
> #--enter activation loop
> ACTIVATED=no
> TIMER=15
> while [ $TIMER -ge 0 ]; do
> R=$(isActivated "$VOL")
> if [ "$R" == "enabled" ]; then
> ACTIVATED=yes
> break
> fi
> sleep 1
> TIMER=$(( TIMER-1 ))
> done
> if [ "$ACTIVATED" == "no" ]; then
> echo "$VOL: not activated on $MY_HOSTNAME"
> exit 5 #--lsb: not running
> fi
>
> #--enter start loop
> /usr/bin/vdo start -n $VOL
> ONLINE=no
> TIMER=15
> while [ $TIMER -ge 0 ]; do
> R=$(isOnline "$VOL")
> if [ "$R" == "online" ]; then
> ONLINE=yes
> break
> fi
> sleep 1
> TIMER=$(( TIMER-1 ))
> done
> if [ "$ONLINE" == "yes" ]; then
> echo "$VOL: started on $MY_HOSTNAME"
> exit 0 #--lsb: success
> else
> echo "$VOL: not started on $MY_HOSTNAME (unknown
> problem)"
> exit 0 #--lsb: unknown problem
> fi
> ;;
> stop)
>
> #--check current status
> R=$(isOnline "$VOL")
> if [ $? -ne 0 ]; then
> echo "error occurred checking $VOL status on $MY_HOSTNAME"
> exit 0
> fi
>
> if [ "$R" == "not" ]; then
> echo "not started on $MY_HOSTNAME"
> exit 0 #--lsb: success
> fi
>
> #--enter stop loop
> /usr/bin/vdo stop -n $VOL
> ONLINE=yes
> TIMER=15
> while [ $TIMER -ge 0 ]; do
> R=$(isOnline "$VOL")
> if [ "$R" == "not" ]; then
> ONLINE=no
> break
> fi
> sleep 1
> TIMER=$(( TIMER-1 ))
> done
> if [ "$ONLINE" == "no" ]; then
> echo "$VOL: stopped on $MY_HOSTNAME"
> exit 0 #--lsb:success
> else
> echo "$VOL: failed to stop on $MY_HOSTNAME (unknown
> problem)"
> exit 0
> fi
> ;;
> status)
> R=$(isOnline "$VOL")
> if [ $? -ne 0 ]; then
> echo "error occurred checking $VOL status on $MY_HOSTNAME"
> exit 5
> fi
> if [ "$R" == "online" ]; then
> echo "$VOL started on $MY_HOSTNAME"
> exit 0 #--lsb: success
> else
> echo "$VOL not started on $MY_HOSTNAME"
> exit 3 #--lsb: not running
> fi
> ;;
>
> esac
>
>
>
> > -----Original Message-----
> > From: Users <users-bounces at clusterlabs.org> On Behalf Of Andrei
> > Borzenkov
> > Sent: Monday, May 17, 2021 12:49 PM
> > To: users at clusterlabs.org
> > Subject: Re: [ClusterLabs] DRBD + VDO HowTo?
> >
> > On 17.05.2021 18:18, Eric Robinson wrote:
> > > To Strahil and Klaus –
> > >
> > > I created the vdo devices using default parameters, so ‘auto’ mode
> > > was
> > selected by default. vdostatus shows that the current mode is async.
> > The underlying drbd devices are running protocol C, so I assume that
> > vdo should be changed to sync mode?
> > >
> > > The VDO service is disabled and is solely under the control of
> > > Pacemaker,
> > but I have been unable to get a resource agent to work reliably. I
> > have two nodes. Under normal operation, Node A is primary for disk
> > drbd0, and device
> > vdo0 rides on top of that. Node B is primary for disk drbd1 and device
> > vdo1 rides on top of that. In the event of a node failure, the vdo
> > device and the underlying drbd disk should migrate to the other node,
> > and then that node will be primary for both drbd disks and both vdo
> devices.
> > >
> > > The default systemd vdo service does not work because it uses the
> > > –all flag
> > and starts/stops all vdo devices. I noticed that there is also a
> > vdo-start-by- dev.service, but there is no documentation on how to use
> > it. I wrote my own vdo-by-dev system service, but that did not work
> > reliably either. Then I noticed that there is already an OCF resource
> > agent named vdo-vol, but that did not work either. I finally tried
> > writing my own OCF-compliant RA, and then I tried writing an
> > LSB-compliant script, but none of those worked very well.
> > >
> >
> > You continue to write novels instead of simply showing your resource
> > agent, your configuration and logs.
> >
> > > My big problem is that I don’t understand how Pacemaker uses the
> > monitor action. Pacemaker would often fail vdo resources because the
> > monitor action received an error when it ran on the standby node. For
> > example, when Node A is primary for disk drbd1 and device vdo1,
> > Pacemaker would fail device vdo1 because when it ran the monitor
> > action on Node B, the RA reported an error. But OF COURSE it would
> > report an error, because disk drbd1 is secondary on that node, and is
> > therefore inaccessible to the vdo driver. I DON’T UNDERSTAND.
> > >
> >
> > May be your definition of "error" does not match pacemaker definition
> > of "error". It is hard to comment without seeing code.
> >
> > > -Eric
> > >
> > >
> > >
> > > From: Strahil Nikolov <hunter86_bg at yahoo.com>
> > > Sent: Monday, May 17, 2021 5:09 AM
> > > To: kwenning at redhat.com; Klaus Wenninger <kwenning at redhat.com>;
> > > Cluster Labs - All topics related to open-source clustering welcomed
> > > <users at clusterlabs.org>; Eric Robinson <eric.robinson at psmnv.com>
> > > Subject: Re: [ClusterLabs] DRBD + VDO HowTo?
> > >
> > > Have you tried to set VDO in async mode ?
> > >
> > > Best Regards,
> > > Strahil Nikolov
> > > On Mon, May 17, 2021 at 8:57, Klaus Wenninger
> > > <kwenning at redhat.com<mailto:kwenning at redhat.com>> wrote:
> > > Did you try VDO in sync-mode for the case the flush-fua stuff isn't
> > > working through the layers?
> > > Did you check that VDO-service is disabled and solely under
> > > pacemaker-control and that the dependencies are set correctly?
> > >
> > > Klaus
> > >
> > > On 5/17/21 6:17 AM, Eric Robinson wrote:
> > >
> > > Yes, DRBD is working fine.
> > >
> > >
> > >
> > > From: Strahil Nikolov
> > > <hunter86_bg at yahoo.com><mailto:hunter86_bg at yahoo.com>
> > > Sent: Sunday, May 16, 2021 6:06 PM
> > > To: Eric Robinson
> > > <eric.robinson at psmnv.com><mailto:eric.robinson at psmnv.com>;
> Cluster
> > > Labs - All topics related to open-source clustering welcomed
> > > <users at clusterlabs.org><mailto:users at clusterlabs.org>
> > > Subject: RE: [ClusterLabs] DRBD + VDO HowTo?
> > >
> > >
> > >
> > > Are you sure that the DRBD is working properly ?
> > >
> > >
> > >
> > > Best Regards,
> > >
> > > Strahil Nikolov
> > >
> > > On Mon, May 17, 2021 at 0:32, Eric Robinson
> > >
> > > <eric.robinson at psmnv.com<mailto:eric.robinson at psmnv.com>> wrote:
> > >
> > > Okay, it turns out I was wrong. I thought I had it working, but I
> > > keep running
> > into problems. Sometimes when I demote a DRBD resource on Node A and
> > promote it on Node B, and I try to mount the filesystem, the system
> > complains that it cannot read the superblock. But when I move the DRBD
> > primary back to Node A, the file system is mountable again. Also, I
> > have problems with filesystems not mounting because the vdo devices
> > are not present. All kinds of issues.
> > >
> > >
> > >
> > >
> > >
> > > From: Users
> > > <users-bounces at clusterlabs.org<mailto:users-
> bounces at clusterlabs.org>
> > > >
> > > On Behalf Of Eric Robinson
> > > Sent: Friday, May 14, 2021 3:55 PM
> > > To: Strahil Nikolov
> > > <hunter86_bg at yahoo.com<mailto:hunter86_bg at yahoo.com>>; Cluster
> > Labs -
> > > All topics related to open-source clustering welcomed
> > > <users at clusterlabs.org<mailto:users at clusterlabs.org>>
> > > Subject: Re: [ClusterLabs] DRBD + VDO HowTo?
> > >
> > >
> > >
> > >
> > >
> > > Okay, I have it working now. The default systemd service definitions
> > > did
> > not work, so I created my own.
> > >
> > >
> > >
> > >
> > >
> > > From: Strahil Nikolov
> > > <hunter86_bg at yahoo.com<mailto:hunter86_bg at yahoo.com>>
> > > Sent: Friday, May 14, 2021 3:41 AM
> > > To: Eric Robinson
> > > <eric.robinson at psmnv.com<mailto:eric.robinson at psmnv.com>>;
> Cluster
> > > Labs - All topics related to open-source clustering welcomed
> > > <users at clusterlabs.org<mailto:users at clusterlabs.org>>
> > > Subject: RE: [ClusterLabs] DRBD + VDO HowTo?
> > >
> > >
> > >
> > > There is no VDO RA according to my knowledge, but you can use
> > > systemd
> > service as a resource.
> > >
> > >
> > >
> > > Yet, the VDO service that comes with thr OS is a generic one and
> > > controlls
> > all VDOs - so you need to create your own vdo service.
> > >
> > >
> > >
> > > Best Regards,
> > >
> > > Strahil Nikolov
> > >
> > > On Fri, May 14, 2021 at 6:55, Eric Robinson
> > >
> > > <eric.robinson at psmnv.com<mailto:eric.robinson at psmnv.com>> wrote:
> > >
> > > I created the VDO volumes fine on the drbd devices, formatted them
> > > as xfs
> > filesystems, created cluster filesystem resources, and the cluster us
> > using them. But the cluster won’t fail over. Is there a VDO cluster RA
> > out there somewhere already?
> > >
> > >
> > >
> > >
> > >
> > > From: Strahil Nikolov
> > > <hunter86_bg at yahoo.com<mailto:hunter86_bg at yahoo.com>>
> > > Sent: Thursday, May 13, 2021 10:07 PM
> > > To: Cluster Labs - All topics related to open-source clustering
> > > welcomed <users at clusterlabs.org<mailto:users at clusterlabs.org>>; Eric
> > > Robinson
> > <eric.robinson at psmnv.com<mailto:eric.robinson at psmnv.com>>
> > > Subject: Re: [ClusterLabs] DRBD + VDO HowTo?
> > >
> > >
> > >
> > > For DRBD there is enough info, so let's focus on VDO.
> > >
> > > There is a systemd service that starts all VDOs on the system. You
> > > can
> > create the VDO once drbs is open for writes and then you can create
> > your own systemd '.service' file which can be used as a cluster resource.
> > >
> > >
> > > Best Regards,
> > >
> > > Strahil Nikolov
> > >
> > >
> > >
> > > On Fri, May 14, 2021 at 2:33, Eric Robinson
> > >
> > > <eric.robinson at psmnv.com<mailto:eric.robinson at psmnv.com>> wrote:
> > >
> > > Can anyone point to a document on how to use VDO de-duplication with
> > DRBD? Linbit has a blog page about it, but it was last updated 6 years
> > ago and the embedded links are dead.
> > >
> > >
> > >
> > > https://linbit.com/blog/albireo-virtual-data-optimizer-vdo-on-drbd/
> > >
> > >
> > >
> > > -Eric
> > >
> > >
> > >
> > >
> > >
> > >
> > >
> > >
> > >
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