Red Hat Summit Red Hat SummitSupportConsoleDevelopersStart a trialContact

Chapter 8. GFS2 file systems in a cluster

Use the following administrative procedures to configure GFS2 file systems in a Red Hat high availability cluster.

8.1. Configuring a GFS2 file system in a cluster
Copy link

You can set up a Pacemaker cluster that includes GFS2 file systems with the following procedure. In this example, you create three GFS2 file systems on three logical volumes in a two-node cluster.

Prerequisites

  • Install and start the cluster software on both cluster nodes and create a basic two-node cluster.
  • Configure fencing for the cluster.

For information about creating a Pacemaker cluster and configuring fencing for the cluster, see Creating a Red Hat High-Availability cluster with Pacemaker.

Procedure

  1. On both nodes in the cluster, enable the repository for Resilient Storage that corresponds to your system architecture. For example, to enable the Resilient Storage repository for an x86_64 system, you can enter the following subscription-manager command: 

    # subscription-manager repos --enable=rhel-9-for-x86_64-resilientstorage-rpms
    Copy to Clipboard Toggle word wrap

    Note that the Resilient Storage repository is a superset of the High Availability repository. If you enable the Resilient Storage repository you do not also need to enable the High Availability repository.

  2. On both nodes of the cluster, install the lvm2-lockd, gfs2-utils, and dlm packages. To support these packages, you must be subscribed to the AppStream channel and the Resilient Storage channel. 

    # dnf install lvm2-lockd gfs2-utils dlm
    Copy to Clipboard Toggle word wrap

  3. On both nodes of the cluster, set the use_lvmlockd configuration option in the /etc/lvm/lvm.conf file to use_lvmlockd=1. 

    ...
use_lvmlockd = 1
...
    Copy to Clipboard Toggle word wrap

  4. Set the global Pacemaker parameter no-quorum-policy to freeze.

    Note

    By default, the value of no-quorum-policy is set to stop, indicating that once quorum is lost, all the resources on the remaining partition will immediately be stopped. Typically this default is the safest and most optimal option, but unlike most resources, GFS2 requires quorum to function. When quorum is lost both the applications using the GFS2 mounts and the GFS2 mount itself cannot be correctly stopped. Any attempts to stop these resources without quorum will fail which will ultimately result in the entire cluster being fenced every time quorum is lost.

    To address this situation, set no-quorum-policy to freeze when GFS2 is in use. This means that when quorum is lost, the remaining partition will do nothing until quorum is regained. 

    [root@z1 ~]# pcs property set no-quorum-policy=freeze
    Copy to Clipboard Toggle word wrap

  5. Set up a dlm resource. This is a required dependency for configuring a GFS2 file system in a cluster. This example creates the dlm resource as part of a resource group named locking. 

    [root@z1 ~]# pcs resource create dlm --group locking ocf:pacemaker:controld op monitor interval=30s on-fail=fence
    Copy to Clipboard Toggle word wrap

  6. Clone the locking resource group so that the resource group can be active on both nodes of the cluster. 

    [root@z1 ~]# pcs resource clone locking interleave=true
    Copy to Clipboard Toggle word wrap

  7. Set up an lvmlockd resource as part of the locking resource group. 

    [root@z1 ~]# pcs resource create lvmlockd --group locking ocf:heartbeat:lvmlockd op monitor interval=30s on-fail=fence
    Copy to Clipboard Toggle word wrap

  8. Check the status of the cluster to ensure that the locking resource group has started on both nodes of the cluster. 

    [root@z1 ~]# pcs status --full
Cluster name: my_cluster
[...]

Online: [ z1.example.com (1) z2.example.com (2) ]

Full list of resources:

 smoke-apc      (stonith:fence_apc):    Started z1.example.com
 Clone Set: locking-clone [locking]
     Resource Group: locking:0
         dlm    (ocf::pacemaker:controld):      Started z1.example.com
         lvmlockd       (ocf::heartbeat:lvmlockd):      Started z1.example.com
     Resource Group: locking:1
         dlm    (ocf::pacemaker:controld):      Started z2.example.com
         lvmlockd       (ocf::heartbeat:lvmlockd):      Started z2.example.com
     Started: [ z1.example.com z2.example.com ]
    Copy to Clipboard Toggle word wrap

  9. On one node of the cluster, create two shared volume groups. One volume group will contain two GFS2 file systems, and the other volume group will contain one GFS2 file system.

    Note

    If your LVM volume group contains one or more physical volumes that reside on remote block storage, such as an iSCSI target, Red Hat recommends that you ensure that the service starts before Pacemaker starts. For information about configuring startup order for a remote physical volume used by a Pacemaker cluster, see Configuring startup order for resource dependencies not managed by Pacemaker.

    The following command creates the shared volume group shared_vg1 on /dev/vdb. 

    [root@z1 ~]# vgcreate --shared shared_vg1 /dev/vdb
  Physical volume "/dev/vdb" successfully created.
  Volume group "shared_vg1" successfully created
  VG shared_vg1 starting dlm lockspace
  Starting locking.  Waiting until locks are ready...
    Copy to Clipboard Toggle word wrap

    The following command creates the shared volume group shared_vg2 on /dev/vdc. 

    [root@z1 ~]# vgcreate --shared shared_vg2 /dev/vdc
  Physical volume "/dev/vdc" successfully created.
  Volume group "shared_vg2" successfully created
  VG shared_vg2 starting dlm lockspace
  Starting locking.  Waiting until locks are ready...
    Copy to Clipboard Toggle word wrap

  10. On the second node in the cluster:

    1. If the use of a devices file is enabled with the use_devicesfile = 1 parameter in the lvm.conf file, add the shared devices to the devices file This feature is enabled by default. 

      [root@z2 ~]# lvmdevices --adddev /dev/vdb
[root@z2 ~]# lvmdevices --adddev /dev/vdc
      Copy to Clipboard Toggle word wrap

    2. Start the lock manager for each of the shared volume groups. 

      [root@z2 ~]# vgchange --lockstart shared_vg1
  VG shared_vg1 starting dlm lockspace
  Starting locking.  Waiting until locks are ready...
[root@z2 ~]# vgchange --lockstart shared_vg2
  VG shared_vg2 starting dlm lockspace
  Starting locking.  Waiting until locks are ready...
      Copy to Clipboard Toggle word wrap

  11. On one node in the cluster, create the shared logical volumes and format the volumes with a GFS2 file system. One journal is required for each node that mounts the file system. Ensure that you create enough journals for each of the nodes in your cluster. The format of the lock table name is ClusterName:FSName where ClusterName is the name of the cluster for which the GFS2 file system is being created and FSName is the file system name, which must be unique for all lock_dlm file systems over the cluster. 

    [root@z1 ~]# lvcreate --activate sy -L5G -n shared_lv1 shared_vg1
  Logical volume "shared_lv1" created.
[root@z1 ~]# lvcreate --activate sy -L5G -n shared_lv2 shared_vg1
  Logical volume "shared_lv2" created.
[root@z1 ~]# lvcreate --activate sy -L5G -n shared_lv1 shared_vg2
  Logical volume "shared_lv1" created.

[root@z1 ~]# mkfs.gfs2 -j2 -p lock_dlm -t my_cluster:gfs2-demo1 /dev/shared_vg1/shared_lv1
[root@z1 ~]# mkfs.gfs2 -j2 -p lock_dlm -t my_cluster:gfs2-demo2 /dev/shared_vg1/shared_lv2
[root@z1 ~]# mkfs.gfs2 -j2 -p lock_dlm -t my_cluster:gfs2-demo3 /dev/shared_vg2/shared_lv1
    Copy to Clipboard Toggle word wrap

  12. Create an LVM-activate resource for each logical volume to automatically activate that logical volume on all nodes.

    1. Create an LVM-activate resource named sharedlv1 for the logical volume shared_lv1 in volume group shared_vg1. This command also creates the resource group shared_vg1 that includes the resource. In this example, the resource group has the same name as the shared volume group that includes the logical volume. 

      [root@z1 ~]# pcs resource create sharedlv1 --group shared_vg1 ocf:heartbeat:LVM-activate lvname=shared_lv1 vgname=shared_vg1 activation_mode=shared vg_access_mode=lvmlockd
      Copy to Clipboard Toggle word wrap

    2. Create an LVM-activate resource named sharedlv2 for the logical volume shared_lv2 in volume group shared_vg1. This resource will also be part of the resource group shared_vg1. 

      [root@z1 ~]# pcs resource create sharedlv2 --group shared_vg1 ocf:heartbeat:LVM-activate lvname=shared_lv2 vgname=shared_vg1 activation_mode=shared vg_access_mode=lvmlockd
      Copy to Clipboard Toggle word wrap

    3. Create an LVM-activate resource named sharedlv3 for the logical volume shared_lv1 in volume group shared_vg2. This command also creates the resource group shared_vg2 that includes the resource. 

      [root@z1 ~]# pcs resource create sharedlv3 --group shared_vg2 ocf:heartbeat:LVM-activate lvname=shared_lv1 vgname=shared_vg2 activation_mode=shared vg_access_mode=lvmlockd
      Copy to Clipboard Toggle word wrap

  13. Clone the two new resource groups. 

    [root@z1 ~]# pcs resource clone shared_vg1 interleave=true
[root@z1 ~]# pcs resource clone shared_vg2 interleave=true
    Copy to Clipboard Toggle word wrap

  14. Configure ordering constraints to ensure that the locking resource group that includes the dlm and lvmlockd resources starts first. 

    [root@z1 ~]# pcs constraint order start locking-clone then shared_vg1-clone
Adding locking-clone shared_vg1-clone (kind: Mandatory) (Options: first-action=start then-action=start)
[root@z1 ~]# pcs constraint order start locking-clone then shared_vg2-clone
Adding locking-clone shared_vg2-clone (kind: Mandatory) (Options: first-action=start then-action=start)
    Copy to Clipboard Toggle word wrap

  15. Configure colocation constraints to ensure that the vg1 and vg2 resource groups start on the same node as the locking resource group. 

    [root@z1 ~]# pcs constraint colocation add shared_vg1-clone with locking-clone
[root@z1 ~]# pcs constraint colocation add shared_vg2-clone with locking-clone
    Copy to Clipboard Toggle word wrap

  16. On both nodes in the cluster, verify that the logical volumes are active. There may be a delay of a few seconds. 

    [root@z1 ~]# lvs
  LV         VG          Attr       LSize
  shared_lv1 shared_vg1  -wi-a----- 5.00g
  shared_lv2 shared_vg1  -wi-a----- 5.00g
  shared_lv1 shared_vg2  -wi-a----- 5.00g

[root@z2 ~]# lvs
  LV         VG          Attr       LSize
  shared_lv1 shared_vg1  -wi-a----- 5.00g
  shared_lv2 shared_vg1  -wi-a----- 5.00g
  shared_lv1 shared_vg2  -wi-a----- 5.00g
    Copy to Clipboard Toggle word wrap

  17. Create a file system resource to automatically mount each GFS2 file system on all nodes.

    You should not add the file system to the /etc/fstab file because it will be managed as a Pacemaker cluster resource. Mount options can be specified as part of the resource configuration with options=options. Run the pcs resource describe Filesystem command to display the full configuration options.

    The following commands create the file system resources. These commands add each resource to the resource group that includes the logical volume resource for that file system. 

    [root@z1 ~]# pcs resource create sharedfs1 --group shared_vg1 ocf:heartbeat:Filesystem device="/dev/shared_vg1/shared_lv1" directory="/mnt/gfs1" fstype="gfs2" options=noatime op monitor interval=10s on-fail=fence
[root@z1 ~]# pcs resource create sharedfs2 --group shared_vg1 ocf:heartbeat:Filesystem device="/dev/shared_vg1/shared_lv2" directory="/mnt/gfs2" fstype="gfs2" options=noatime op monitor interval=10s on-fail=fence
[root@z1 ~]# pcs resource create sharedfs3 --group shared_vg2 ocf:heartbeat:Filesystem device="/dev/shared_vg2/shared_lv1" directory="/mnt/gfs3" fstype="gfs2" options=noatime op monitor interval=10s on-fail=fence
    Copy to Clipboard Toggle word wrap

Verification

  1. Verify that the GFS2 file systems are mounted on both nodes of the cluster. 

    [root@z1 ~]# mount | grep gfs2
/dev/mapper/shared_vg1-shared_lv1 on /mnt/gfs1 type gfs2 (rw,noatime,seclabel)
/dev/mapper/shared_vg1-shared_lv2 on /mnt/gfs2 type gfs2 (rw,noatime,seclabel)
/dev/mapper/shared_vg2-shared_lv1 on /mnt/gfs3 type gfs2 (rw,noatime,seclabel)

[root@z2 ~]# mount | grep gfs2
/dev/mapper/shared_vg1-shared_lv1 on /mnt/gfs1 type gfs2 (rw,noatime,seclabel)
/dev/mapper/shared_vg1-shared_lv2 on /mnt/gfs2 type gfs2 (rw,noatime,seclabel)
/dev/mapper/shared_vg2-shared_lv1 on /mnt/gfs3 type gfs2 (rw,noatime,seclabel)
    Copy to Clipboard Toggle word wrap

  2. Check the status of the cluster. 

    [root@z1 ~]# pcs status --full
Cluster name: my_cluster
[...]

Full list of resources:

 smoke-apc      (stonith:fence_apc):    Started z1.example.com
 Clone Set: locking-clone [locking]
     Resource Group: locking:0
         dlm    (ocf::pacemaker:controld):      Started z2.example.com
         lvmlockd       (ocf::heartbeat:lvmlockd):      Started z2.example.com
     Resource Group: locking:1
         dlm    (ocf::pacemaker:controld):      Started z1.example.com
         lvmlockd       (ocf::heartbeat:lvmlockd):      Started z1.example.com
     Started: [ z1.example.com z2.example.com ]
 Clone Set: shared_vg1-clone [shared_vg1]
     Resource Group: shared_vg1:0
         sharedlv1      (ocf::heartbeat:LVM-activate):  Started z2.example.com
         sharedlv2      (ocf::heartbeat:LVM-activate):  Started z2.example.com
         sharedfs1      (ocf::heartbeat:Filesystem):    Started z2.example.com
         sharedfs2      (ocf::heartbeat:Filesystem):    Started z2.example.com
     Resource Group: shared_vg1:1
         sharedlv1      (ocf::heartbeat:LVM-activate):  Started z1.example.com
         sharedlv2      (ocf::heartbeat:LVM-activate):  Started z1.example.com
         sharedfs1      (ocf::heartbeat:Filesystem):    Started z1.example.com
         sharedfs2      (ocf::heartbeat:Filesystem):    Started z1.example.com
     Started: [ z1.example.com z2.example.com ]
 Clone Set: shared_vg2-clone [shared_vg2]
     Resource Group: shared_vg2:0
         sharedlv3      (ocf::heartbeat:LVM-activate):  Started z2.example.com
         sharedfs3      (ocf::heartbeat:Filesystem):    Started z2.example.com
     Resource Group: shared_vg2:1
         sharedlv3      (ocf::heartbeat:LVM-activate):  Started z1.example.com
         sharedfs3      (ocf::heartbeat:Filesystem):    Started z1.example.com
     Started: [ z1.example.com z2.example.com ]

...
    Copy to Clipboard Toggle word wrap

You can create a Pacemaker cluster that includes a LUKS encrypted GFS2 file system with the following procedure. In this example, you create one GFS2 file systems on a logical volume and encrypt the file system. Encrypted GFS2 file systems are supported using the crypt resource agent, which provides support for LUKS encryption.

There are three parts to this procedure:

  • Configuring a shared logical volume in a Pacemaker cluster
  • Encrypting the logical volume and creating a crypt resource
  • Formatting the encrypted logical volume with a GFS2 file system and creating a file system resource for the cluster

Prerequisites

  • Install and start the cluster software on two cluster nodes and create a basic two-node cluster.
  • Configure fencing for the cluster.

For information about creating a Pacemaker cluster and configuring fencing for the cluster, see Creating a Red Hat High-Availability cluster with Pacemaker.

Procedure

  1. On both nodes in the cluster, enable the repository for Resilient Storage that corresponds to your system architecture. For example, to enable the Resilient Storage repository for an x86_64 system, you can enter the following subscription-manager command: 

    # subscription-manager repos --enable=rhel-9-for-x86_64-resilientstorage-rpms
    Copy to Clipboard Toggle word wrap

    Note that the Resilient Storage repository is a superset of the High Availability repository. If you enable the Resilient Storage repository you do not also need to enable the High Availability repository.

  2. On both nodes of the cluster, install the lvm2-lockd, gfs2-utils, and dlm packages. To support these packages, you must be subscribed to the AppStream channel and the Resilient Storage channel. 

    # dnf install lvm2-lockd gfs2-utils dlm
    Copy to Clipboard Toggle word wrap

  3. On both nodes of the cluster, set the use_lvmlockd configuration option in the /etc/lvm/lvm.conf file to use_lvmlockd=1. 

    ...
use_lvmlockd = 1
...
    Copy to Clipboard Toggle word wrap

  4. Set the global Pacemaker parameter no-quorum-policy to freeze.

    Note

    By default, the value of no-quorum-policy is set to stop, indicating that when quorum is lost, all the resources on the remaining partition will immediately be stopped. Typically this default is the safest and most optimal option, but unlike most resources, GFS2 requires quorum to function. When quorum is lost both the applications using the GFS2 mounts and the GFS2 mount itself cannot be correctly stopped. Any attempts to stop these resources without quorum will fail which will ultimately result in the entire cluster being fenced every time quorum is lost.

    To address this situation, set no-quorum-policy to freeze when GFS2 is in use. This means that when quorum is lost, the remaining partition will do nothing until quorum is regained. 

    [root@z1 ~]# pcs property set no-quorum-policy=freeze
    Copy to Clipboard Toggle word wrap

  5. Set up a dlm resource. This is a required dependency for configuring a GFS2 file system in a cluster. This example creates the dlm resource as part of a resource group named locking. 

    [root@z1 ~]# pcs resource create dlm --group locking ocf:pacemaker:controld op monitor interval=30s on-fail=fence
    Copy to Clipboard Toggle word wrap

  6. Clone the locking resource group so that the resource group can be active on both nodes of the cluster. 

    [root@z1 ~]# pcs resource clone locking interleave=true
    Copy to Clipboard Toggle word wrap

  7. Set up an lvmlockd resource as part of the group locking. 

    [root@z1 ~]# pcs resource create lvmlockd --group locking ocf:heartbeat:lvmlockd op monitor interval=30s on-fail=fence
    Copy to Clipboard Toggle word wrap

  8. Check the status of the cluster to ensure that the locking resource group has started on both nodes of the cluster. 

    [root@z1 ~]# pcs status --full
Cluster name: my_cluster
[...]

Online: [ z1.example.com (1) z2.example.com (2) ]

Full list of resources:

 smoke-apc      (stonith:fence_apc):    Started z1.example.com
 Clone Set: locking-clone [locking]
     Resource Group: locking:0
         dlm    (ocf::pacemaker:controld):      Started z1.example.com
         lvmlockd       (ocf::heartbeat:lvmlockd):      Started z1.example.com
     Resource Group: locking:1
         dlm    (ocf::pacemaker:controld):      Started z2.example.com
         lvmlockd       (ocf::heartbeat:lvmlockd):      Started z2.example.com
     Started: [ z1.example.com z2.example.com ]
    Copy to Clipboard Toggle word wrap

  9. On one node of the cluster, create a shared volume group.

    Note

    If your LVM volume group contains one or more physical volumes that reside on remote block storage, such as an iSCSI target, Red Hat recommends that you ensure that the service starts before Pacemaker starts. For information about configuring startup order for a remote physical volume used by a Pacemaker cluster, see Configuring startup order for resource dependencies not managed by Pacemaker.

    The following command creates the shared volume group shared_vg1 on /dev/sda1. 

    [root@z1 ~]# vgcreate --shared shared_vg1 /dev/sda1
  Physical volume "/dev/sda1" successfully created.
  Volume group "shared_vg1" successfully created
  VG shared_vg1 starting dlm lockspace
  Starting locking.  Waiting until locks are ready...
    Copy to Clipboard Toggle word wrap

  10. On the second node in the cluster:

    1. If the use of a devices file is enabled with the use_devicesfile = 1 parameter in the lvm.conf file, add the shared device to the devices file on the second node in the cluster. This feature is enabled by default. 

      [root@z2 ~]# lvmdevices --adddev /dev/sda1
      Copy to Clipboard Toggle word wrap

    2. Start the lock manager for the shared volume group. 

      [root@z2 ~]# vgchange --lockstart shared_vg1
  VG shared_vg1 starting dlm lockspace
  Starting locking.  Waiting until locks are ready...
      Copy to Clipboard Toggle word wrap

  11. On one node in the cluster, create the shared logical volume. 

    [root@z1 ~]# lvcreate --activate sy -L5G -n shared_lv1 shared_vg1
  Logical volume "shared_lv1" created.
    Copy to Clipboard Toggle word wrap

  12. Create an LVM-activate resource for the logical volume to automatically activate the logical volume on all nodes.

    The following command creates an LVM-activate resource named sharedlv1 for the logical volume shared_lv1 in volume group shared_vg1. This command also creates the resource group shared_vg1 that includes the resource. In this example, the resource group has the same name as the shared volume group that includes the logical volume. 

    [root@z1 ~]# pcs resource create sharedlv1 --group shared_vg1 ocf:heartbeat:LVM-activate lvname=shared_lv1 vgname=shared_vg1 activation_mode=shared vg_access_mode=lvmlockd
    Copy to Clipboard Toggle word wrap

  13. Clone the new resource group. 

    [root@z1 ~]# pcs resource clone shared_vg1 interleave=true
    Copy to Clipboard Toggle word wrap

  14. Configure an ordering constraints to ensure that the locking resource group that includes the dlm and lvmlockd resources starts first. 

    [root@z1 ~]# pcs constraint order start locking-clone then shared_vg1-clone
Adding locking-clone shared_vg1-clone (kind: Mandatory) (Options: first-action=start then-action=start)
    Copy to Clipboard Toggle word wrap

  15. Configure a colocation constraints to ensure that the vg1 and vg2 resource groups start on the same node as the locking resource group. 

    [root@z1 ~]# pcs constraint colocation add shared_vg1-clone with locking-clone
    Copy to Clipboard Toggle word wrap

Verification

On both nodes in the cluster, verify that the logical volume is active. There may be a delay of a few seconds. 

[root@z1 ~]# lvs
  LV         VG          Attr       LSize
  shared_lv1 shared_vg1  -wi-a----- 5.00g

[root@z2 ~]# lvs
  LV         VG          Attr       LSize
  shared_lv1 shared_vg1  -wi-a----- 5.00g
Copy to Clipboard Toggle word wrap

Prerequisites

  • You have configured a shared logical volume in a Pacemaker cluster.

Procedure

  1. On one node in the cluster, create a new file that will contain the crypt key and set the permissions on the file so that it is readable only by root. 

    [root@z1 ~]# touch /etc/crypt_keyfile
[root@z1 ~]# chmod 600 /etc/crypt_keyfile
    Copy to Clipboard Toggle word wrap

  2. Create the crypt key. 

    [root@z1 ~]# dd if=/dev/urandom bs=4K count=1 of=/etc/crypt_keyfile
1+0 records in
1+0 records out
4096 bytes (4.1 kB, 4.0 KiB) copied, 0.000306202 s, 13.4 MB/s
[root@z1 ~]# scp /etc/crypt_keyfile root@z2.example.com:/etc/
    Copy to Clipboard Toggle word wrap

  3. Distribute the crypt keyfile to the other nodes in the cluster, using the -p parameter to preserve the permissions you set. 

    [root@z1 ~]# scp -p /etc/crypt_keyfile root@z2.example.com:/etc/
    Copy to Clipboard Toggle word wrap

  4. Create the encrypted device on the LVM volume where you will configure the encrypted GFS2 file system. 

    [root@z1 ~]# cryptsetup luksFormat /dev/shared_vg1/shared_lv1 --type luks2 --key-file=/etc/crypt_keyfile
WARNING!
========
This will overwrite data on /dev/shared_vg1/shared_lv1 irrevocably.

Are you sure? (Type 'yes' in capital letters): YES
    Copy to Clipboard Toggle word wrap

  5. Create the crypt resource as part of the shared_vg1 volume group. 

    [root@z1 ~]# pcs resource create crypt --group shared_vg1 ocf:heartbeat:crypt crypt_dev="luks_lv1" crypt_type=luks2 key_file=/etc/crypt_keyfile encrypted_dev="/dev/shared_vg1/shared_lv1"
    Copy to Clipboard Toggle word wrap

Verification

Ensure that the crypt resource has created the crypt device, which in this example is /dev/mapper/luks_lv1. 

[root@z1 ~]# ls -l /dev/mapper/
...
lrwxrwxrwx 1 root root 7 Mar 4 09:52 luks_lv1 -> ../dm-3
...
Copy to Clipboard Toggle word wrap

Prerequisites

  • You have encrypted the logical volume and created a crypt resource.

Procedure

  1. On one node in the cluster, format the volume with a GFS2 file system. One journal is required for each node that mounts the file system. Ensure that you create enough journals for each of the nodes in your cluster. The format of the lock table name is ClusterName:FSName where ClusterName is the name of the cluster for which the GFS2 file system is being created and FSName is the file system name, which must be unique for all lock_dlm file systems over the cluster. 

    [root@z1 ~]# mkfs.gfs2 -j3 -p lock_dlm -t my_cluster:gfs2-demo1 /dev/mapper/luks_lv1
/dev/mapper/luks_lv1 is a symbolic link to /dev/dm-3
This will destroy any data on /dev/dm-3
Are you sure you want to proceed? [y/n] y
Discarding device contents (may take a while on large devices): Done
Adding journals: Done
Building resource groups: Done
Creating quota file: Done
Writing superblock and syncing: Done
Device:                    /dev/mapper/luks_lv1
Block size:                4096
Device size:               4.98 GB (1306624 blocks)
Filesystem size:           4.98 GB (1306622 blocks)
Journals:                  3
Journal size:              16MB
Resource groups:           23
Locking protocol:          "lock_dlm"
Lock table:                "my_cluster:gfs2-demo1"
UUID:                      de263f7b-0f12-4d02-bbb2-56642fade293
    Copy to Clipboard Toggle word wrap

  2. Create a file system resource to automatically mount the GFS2 file system on all nodes.

    Do not add the file system to the /etc/fstab file because it will be managed as a Pacemaker cluster resource. Mount options can be specified as part of the resource configuration with options=options. Run the pcs resource describe Filesystem command for full configuration options.

    The following command creates the file system resource. This command adds the resource to the resource group that includes the logical volume resource for that file system. 

    [root@z1 ~]# pcs resource create sharedfs1 --group shared_vg1 ocf:heartbeat:Filesystem device="/dev/mapper/luks_lv1" directory="/mnt/gfs1" fstype="gfs2" options=noatime op monitor interval=10s on-fail=fence
    Copy to Clipboard Toggle word wrap

Verification

  1. Verify that the GFS2 file system is mounted on both nodes of the cluster. 

    [root@z1 ~]# mount | grep gfs2
/dev/mapper/luks_lv1 on /mnt/gfs1 type gfs2 (rw,noatime,seclabel)

[root@z2 ~]# mount | grep gfs2
/dev/mapper/luks_lv1 on /mnt/gfs1 type gfs2 (rw,noatime,seclabel)
    Copy to Clipboard Toggle word wrap

  2. Check the status of the cluster. 

    [root@z1 ~]# pcs status --full
Cluster name: my_cluster
[...]

Full list of resources:

  smoke-apc      (stonith:fence_apc):    Started z1.example.com
  Clone Set: locking-clone [locking]
      Resource Group: locking:0
          dlm    (ocf::pacemaker:controld):      Started z2.example.com
          lvmlockd       (ocf::heartbeat:lvmlockd):      Started z2.example.com
      Resource Group: locking:1
          dlm    (ocf::pacemaker:controld):      Started z1.example.com
          lvmlockd       (ocf::heartbeat:lvmlockd):      Started z1.example.com
     Started: [ z1.example.com z2.example.com ]
  Clone Set: shared_vg1-clone [shared_vg1]
     Resource Group: shared_vg1:0
             sharedlv1      (ocf::heartbeat:LVM-activate):  Started z2.example.com
             crypt       (ocf::heartbeat:crypt) Started z2.example.com
             sharedfs1      (ocf::heartbeat:Filesystem):    Started z2.example.com
    Resource Group: shared_vg1:1
             sharedlv1      (ocf::heartbeat:LVM-activate):  Started z1.example.com
             crypt      (ocf::heartbeat:crypt)  Started z1.example.com
             sharedfs1      (ocf::heartbeat:Filesystem):    Started z1.example.com
          Started:  [z1.example.com z2.example.com ]
...
    Copy to Clipboard Toggle word wrap
Back to top
Red Hat logoGithubredditYoutubeTwitter

Learn

Try, buy, & sell

Communities

About Red Hat Documentation

We help Red Hat users innovate and achieve their goals with our products and services with content they can trust. Explore our recent updates.

Making open source more inclusive

Red Hat is committed to replacing problematic language in our code, documentation, and web properties. For more details, see the Red Hat Blog.

About Red Hat

We deliver hardened solutions that make it easier for enterprises to work across platforms and environments, from the core datacenter to the network edge.

Theme

© 2025 Red Hat