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NFS on ZFS HA Cluster

Build a high-available dual-controller storage array using open-source technologies.
This solution should be capable of presenting shared storage to NFS client and can be expanded to iSCSI and FCoE.

What is needed:

  • 2 nodes with A LOT of memory.
  • Fast storage that is directly attached to each node.
  • Root access.
  • The ZFS filesystem configured via the ZFS on Linux repository.
  • Familiarity with basic ZFS operations: zpool/zfs filesystem creation and modification.
  • Understanding of network under RHEL Linux.

These steps describe the construction of a two host, single JBOD cluster that manages a single ZFS pool.

On both nodes:

Get EPEL and ZFS repositories

yum install -y epel-release
yum install -y http://download.zfsonlinux.org/epel/zfs-release.el7_5.noarch.rpm
yum update -y
yum install -y kernel-devel zfs
systemctl preset zfs-import-cache zfs-import-scan zfs-mount zfs-share zfs-zed zfs.target
systemctl enable zfs-import-scan
systemctl start zfs-import-scan

Add some clustering requirements:

yum install -y pcs fence-agents-all device-mapper-multipath nfs-utils
touch /etc/multipath.conf
systemctl start multipathd
systemctl enable multipathd

Add each node to the /etc/hosts file.

echo "172.16.100.142 node1" >> /etc/hosts
echo "172.16.100.144 node2" >> /etc/hosts

Set the hacluster password:

passwd hacluster wljgnFAW4fgwEGF21

Add needed heartbeat files

cd /usr/lib/ocf/resource.d/heartbeat/
wget https://raw.githubusercontent.com/clusterapps/stmf-ha/master/heartbeat/ZFS
wget https://github.com/ClusterLabs/resource-agents/raw/master/heartbeat/iSCSITarget
wget https://github.com/ClusterLabs/resource-agents/raw/master/heartbeat/iSCSILogicalUnit
chmod a+x ./ZFS
chmod a+x ./iSCSILogicalUnit
chmod a+x ./iSCSITarget

Update the firewall configuration.

firewall-cmd --add-service=nfs --permanent
firewall-cmd --add-service=high-availability --permanent
firewall-cmd --permanent --add-service=nfs
firewall-cmd --permanent --add-service=mountd
firewall-cmd --permanent --add-service=rpc-bind
firewall-cmd --reload

Enable the services and reboot. This step helps verify all of the services are properly configured on boot.

systemctl enable pcsd
systemctl enable corosync
systemctl enable pacemaker
reboot

On the Primary

Create the pool. You will need the path to the devices. Get them from:

ls -l /dev/disk/by-id/

Run zpool create (Your devices will be different!)
This pool has similar qualities to a RAID5+0. You should build what you need.

zpool create array1 -o ashift=12 -o autoexpand=on -o autoreplace=on -o cachefile=none \
raidz1 /dev/disk/by-id/scsi-35000c500740a6277 /dev/disk/by-id/scsi-35000c5007411d36b /dev/disk/by-id/scsi-35000c5007411cb1b \
raidz1 /dev/disk/by-id/scsi-35000c50076703a9f /dev/disk/by-id/scsi-35000c50070d3a853 /dev/disk/by-id/scsi-35000c50076701f57 \
raidz1 /dev/disk/by-id/scsi-35000c5007411cfa7 /dev/disk/by-id/scsi-35000c5007411d0bf /dev/disk/by-id/scsi-35000c500740a109f \
log mirror /dev/disk/by-id/scsi-35000c5007670107f /dev/disk/by-id/scsi-35000c5007411d467 spare /dev/disk/by-id/scsi-35000c50076bd0c03

Update a few ZFS settings

zfs set acltype=posixacl array1
zfs set atime=off array1
zfs set xattr=sa array1
zfs set compression=lz4 array1

Authorize Cluster

pcs cluster auth node1 node2
pcs cluster setup --start --name NASOne node1 node2

Set some cluster properties and ad the resources

pcs property set no-quorum-policy=ignore
pcs stonith create fence-array1 fence_scsi pcmk_monitor_action="metadata" pcmk_host_list="node1 node2" \
devices="/dev/mapper/35000c5007670107f,/dev/mapper/35000c5007411d467,/dev/mapper/35000c50076bd0c03" \
meta provides=unfencing --group=group-array1
pcs resource create array1-ip IPaddr2 ip=172.16.100.99 cidr_netmask=24 --group group-array1
pcs resource create array1 ZFS pool="array1" importargs="-d /dev/mapper/" op start timeout="90" op stop timeout="90" --group=group-array1
pcs resource defaults resource-stickiness=100

Create and share a ZFS directory.

zfs create array1/nfs1
zfs set sharenfs=rw=@172.16.100.0/24,sync,no_root_squash,no_wdelay array1/nfs1

Enable and start NFS released services.

systemctl enable rpcbind nfs-server
systemctl start rpcbind nfs-server

Check the status of the cluster.

pcs cluster status
pcs status resources
showmount -e localhost

 

 

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