AIX configuration

The AIX configuration used for testing this scenario is depicted in Figure 6-4.

Figure 6-4 Network file system (NFS) in the LPAR environment

In Figure 6-4, one LPAR with the AIX operating system (labelled NFS Server) uses the IBM Virtual I/O Server (VIO Server) software to perform the mapping

AIX External Shared Storage VIO Server POWER Hypervisor S B LPAR p5501p5 Data VIO Server AIX POWER Hypervisor S B LPAR p5502p8 NFS Server VIO Server AIX POWER Hypervisor S B LPAR p5501p4 Data NFS Client NFS Client SAN NFS Network

disk storage is exported from one of the LPARs acting as an NFS server. The other two LPAR nodes act as NFS clients and mount the exported file systems on SAN shared disks storage.

6.3.1 Software installed on the AIX systems

The software installed on the active and standby AIX servers are summarized in Table 6-1.

Table 6-1 Installed software for the active and standby AIX servers

6.3.2 Preparing the shared disk on AIX

Our configuration uses one volume group: nfsdata_vg. The volume groups, logical volumes, and file systems shared by the two network file system (NFS) client nodes are created on the NFS server node. After the file systems are prepared, the volume group on the NFS server can be exported and the two NFS client nodes can mount them.

The smit mkvg fastpath utility was used to create the volume group, as shown in Example 6-1.

Example 6-1 Create a volume group

Add an Original Volume Group

Type or select values in entry fields. Press Enter AFTER making all desired changes.

[Entry Fields] VOLUME GROUP name [nfsdata_vg] Physical partition SIZE in megabytes +

* PHYSICAL VOLUME names [hdisk2] + Force the creation of a volume group? no +

Software Version

AIX 6.1.4

WebSphere MQ 7.0.1

WebSphere Message Broker 7.0.0

In the Example 6-1 on page 112, an original enhanced-capable volume group named nfsdata_vg is defined on the NFS server node. This volume group contains hdisk2 and has major number 38. The available volume group major number 38 is found by using the lvlstmajor command. After the volume group

has been created, it must be activated to make it available for use by using the

varyonvg command, as shown in Example 6-2.

Example 6-2 Activating the volume group

# varyonvg data_vg

Before the logical volume group can be created, create a log for the logical volume group, as in Example 6-3.

Example 6-3 Creating the log for the logical volume

bash-3.00# mklv -t jfs2log -y lognfsshared_lv nfsdata_vg 600M lognfsshared_lv

bash-3.00# /usr/sbin/logform /dev/lognfsshared_lv logform: destroy /dev/rlognfsshared_lv (y)?y

The mklv command is used to create a logical volume named nfsshared_lv with 50 GB of storage space, on volume group nfsdata_vg, as shown in Example 6-4.

Example 6-4 Create logical volume

bash-3.00# mklv -t jfs2 -y nfsshared_lv nfsdata_vg 50G nfsshared_lv

Next, we use the crfs command to create the file systems on this logical volume. The results is shown in Example 6-5.

Example 6-5 Creating the file system

bash-3.00# crfs -v jfs2 -p rw -d /dev/nfsshared_lv -m /NFSMQHA -A yes File system created successfully.

52426996 kilobytes total disk space. New File System size is 104857600

Finally we mount the file systems to check that we have successfully created the NFS file systems on NFS server node. This is shown in Example 6-6:

Example 6-6 Mount file system

6.3.3 Exporting the file systems using NFS V4 mount

The NFS is a mechanism for storing files on a network. By using NFS, files and directories located on a remote computers can be treated as though they were local.

NFS provides its services through a client-server relationship:

Computers that make their file systems, directories, and other resources available for remote access are called

NFS servers

. The act of making file systems available is called

exporting

.

Computers and their processes that use server resources are referred to as

NFS clients

. After a client mounts a file system that a server exports, the client can access the individual server files.

To export the /NFSMQHA directory on our NFS server p5501p4 and mount that directory on NFS client p5501p5 as the /mnt directory, the exportfs command is used on the NFS server as shown in Example 6-7.

Example 6-7 Export NFS file system

exportfs -i -o access=p5501p5 /NFSMQHA

This command makes the /NFFSMQHA directory available to the client. To complete the process the mount command must also be called on the client nodes. Example 6-8 shows the command used to mount the directory on node 1.

Example 6-8 Mounting the NFS file system on the NFS clients

mount -o vers=4 p5501p4:/NFFSMQHA /mnt

The directories and files in the /NFSMQHA directory on the NFS server appear as the /mnt directory on the NFS clients. This can be checked by using the mount command, as shown in Example 6-9.

Example 6-9 Mount NFS file system results

p5501p5(root)/> mount

node mounted mounted over vfs date options --- --- --- --- --- --- /dev/hd4 / jfs2 Feb 19 23:55 rw,log=/dev/hd8 /dev/hd2 /usr jfs2 Feb 19 23:55 rw,log=/dev/hd8 /dev/hd9var /var jfs2 Feb 19 23:55 rw,log=/dev/hd8 /dev/hd3 /tmp jfs2 Feb 19 23:55 rw,log=/dev/hd8 /dev/hd1 /home jfs2 Feb 19 23:55 rw,log=/dev/hd8 /dev/hd11admin /admin jfs2 Feb 19 23:55 rw,log=/dev/hd8 /proc /proc procfs Feb 19 23:55 rw

/dev/hd10opt /opt jfs2 Feb 19 23:55 rw,log=/dev/hd8 /dev/livedump /var/adm/ras/livedump jfs2 Feb 19 23:55

rw,log=/dev/hd8

/dev/download_lv /download jfs2 Feb 19 23:55 rw,log=/dev/hd8 /dev/test_lv /mydir jfs2 Feb 19 23:55 rw,log=/dev/hd8 p5501p4 /NFSMQHA /mnt nfs4 Feb 19 23:58 vers=4

This process is repeated to mount the same directory on the second NFS client, p5502p8, as the /mnt directory.

In document High Availability in WebSphere Messaging Solutions (Page 127-131)