Chapter 3. Configuring Nodes for IRIS FailSafe

This chapter describes several system administration procedures that must be performed on the nodes in a cluster to prepare and configure them for IRIS FailSafe. These procedures assume that you have done the planning described in Chapter 2, “Planning IRIS FailSafe Configuration.”

The major sections in this chapter are as follows:

Overview of Configuring Nodes for IRIS FailSafe

Performing the system administration procedures required to prepare nodes for IRIS FailSafe involves these steps:

  1. Install required software as described in the section “Installing Required Software.”

  2. Check the setting of two important NVRAM variables as described in the section “Setting NVRAM Variables.”

  3. Create the XLV logical volumes and XFS filesystems required by the highly available applications you plan to run on the cluster. See the section “Creating XLV Logical Volumes and XFS Filesystems.”

  4. Configure the network interfaces on both nodes using the procedure in the section “Configuring Interfaces.”

  5. Configure the serial ports used on each node for the serial connection to the other node by following the procedure in the section “Configuring the Serial Port.”

  6. If the IRIS FailSafe NFS option is used, perform necessary NFS configuration as described in the section “Configuring NFS Filesystems.”

  7. If the IRIS FailSafe Web option is used, configure Netscape servers as described in the section “Configuring a Netscape Server.”

  8. When you are ready configure the nodes so that IRIS FailSafe software starts up when they are rebooted, follow the instructions in the section “Configuring IRIS FailSafe On.”

To complete the configuration of nodes for IRIS FailSafe, you must create and install the IRIS FailSafe configuration file /var/ha/ha.conf as described in Chapter 4, “Creating the IRIS FailSafe Configuration File.”

Installing Required Software

This section explains software installation requirements and procedures for new IRIS FailSafe clusters. To install a new release of IRIX or IRIS FailSafe software on an IRIS FailSafe cluster already in use, see Chapter 7, “Upgrading an IRIS FailSafe Cluster.”

Several categories of software must be installed on each node in a cluster:

Base system software 


IRIX 5.3 with XFS or IRIX 6.2 is required. NFS software is required if the IRIS FailSafe NFS option is used. Netscape server software is required if the IRIS FailSafe Web option is used. RAID software is required if RAID is being used.

Patches 

IRIS FailSafe requires several base system software patches, which are listed in the IRIS FailSafe base software release notes.

IRIS FailSafe software 


The base IRIS FailSafe option product is required. The IRIS FailSafe NFS option is required for failing over filesystems. The IRIS FailSafe Web option is required for failing over Netscape servers.

Disk plexing licenses 


On clusters that use plexed XLV logical volumes on shared disks, a NetLS license is required on nodes running IRIX 5.3 and a FLEXlm license is required on nodes running IRIX 6.2.

The two nodes in a cluster need not be running the same version of IRIX. However, they must run the same version of IRIS FailSafe software.

Follow this procedure for installing software on the nodes in a new cluster:

  1. On one node, follow normal software installation procedures and use inst to install required subsystems that aren't already installed. The required subsystems are listed in Table 3-1. (See “Related Documentation” for guides about inst).

    Table 3-1. Required Software Subsystems

    Product

    Base System Software Subsystems Required by IRIS FailSafe

    IRIS FailSafe Subsystems

    IRIS FailSafe

    For IRIX 5.3: eoe2.sw.xfs, eoe2.sw.xlv, eoe2.sw.xlvplex
    For IRIX 6.2: eoe.sw.xfs, eoe.sw.xlv, eoe.sw.xlvplex
    For FDDI (if used): FDDIXPress.sw.FDDIXPress
    For RAID (if used): raid5.sw.cli

    ha.sw.base or ha_IP22.sw.base

    IRIS FailSafe NFS

    nfs.sw.nfs

    ha_nfs.sw.base

    IRIS FailSafe Web

    ns_httpd.sw.server (Communications server)
    ns_commerce.sw.server (Commerce server)

    ha_www.sw.base


  2. On the same node, install required patches. See the release notes for IRIS FailSafe (called ha_base, ha_nfs, and ha_www) for lists of the required patches.

  3. Install software and patches on the other node by repeating steps 1 and 2 on the other node.

  4. If you are using plexed XLV logical volumes, install a disk plexing license on each node.

    For IRIX 5.3, the license is a NetLS license and it is installed in a non-standard location, /etc/nodelock. For more information, see the Disk Plexing release notes (called plexing).

    For IRIX 6.2, the license is a FLEXlm license and installed in /etc/flexlm/license.dat. For more information see the FLEXlm End User Manual.

  5. If you are using plexed XLV logical volumes, verify that the license has been successfully installed by entering these commands on each node:

    # xlv_mgr
    xlv_mgr> show config
    ...
    Plexing license: present
    ...
    xlv_mgr> quit
    

    The line shown about the plexing license indicates that the plexing license has been successfully installed.

Setting NVRAM Variables

During the hardware installation of IRIS FailSafe nodes, two NVRAM variables must be set:

  • The boot parameter AutoLoad must be set to yes. The IRIS Failsafe software requires the nodes to be automatically booted when they are reset or when the node is powered on.

  • The SCSI IDs of the nodes in an IRIS FailSafe cluster, specified by the scsihostid variable, must be different.

You can check the setting of these variables with these commands:

# nvram AutoLoad 
Y
# nvram scsihostid 
0

To set these variables, use these commands:

# nvram AutoLoad yes 
# nvram scsihostid number

number is the SCSI ID you choose. A node uses its SCSI ID on all buses attached to it. Therefore, you must make sure that no device attached to a node has number as its SCSI unit number.

Creating XLV Logical Volumes and XFS Filesystems

In Chapter 2 you planned the XLV logical volumes and XFS filesystems to be used by highly available applications on the cluster. You can create them by following the instructions in one these guides:

  • Getting Started with XFS Filesystems (IRIX 5.3)

  • IRIX Admin: Disks and Filesystems (IRIX 6.2)

When you create the XLV logical volumes and XFS filesystems you need, some important points to remember are:

  • If the shared disks are not in a CHALLENGE RAID storage system, plexed XLV logical volumes should be created.

  • Each XLV logical volume must be owned by the same node that is the primary node for the highly available applications that use the logical volume (see “Planning Logical Volumes” in Chapter 2). To simplify the management of the nodenames (owners) of volumes on shared disks, follow these recommendations:

    • Work with the volumes on a shared disk from only one node in the cluster.

    • After you initially create all the volumes on one node, you can then selectively change the nodename to the other node afterwards using xlv_mgr.

  • If the XLV logical volumes you create are used as raw volumes (no filesystem) for storing database data, the database system may require that the device names (in /dev/rdsk/xlv and /dev/dsk/xlv) have specific owners, groups, and modes. If this is the case (see the documentation provided by the database vendor), use the chown and chmod commands (see the chown(1) and chmod(1) reference pages) to set the owner, group, and mode as required.

  • No filesystem entries are made in /etc/fstab for XFS filesystems on shared disks; IRIS FailSafe software mounts the filesystems on shared disks. However, to simplify system administration, consider adding comments to /etc/fstab that list the XFS filesystems configured for IRIS FailSafe. Thus, a system administrator who sees mounted IRIS FailSafe filesystems in the output of the df command and looks for the filesystems in the /etc/fstab file will learn that they are filesystems managed by IRIS FailSafe.

  • Be sure to create the mount point directory for each filesystem on both nodes.

Configuring Interfaces

The procedure in this section describes how to configure the public and private interfaces on the nodes in an IRIS FailSafe cluster. The example shown in Figure 3-1 is used in the procedure.

Figure 3-1. Example Interface Configuration


  1. If possible, add every IP address, IP name, and IP alias for both nodes to /etc/hosts on one node.

    For example:

    190.0.2.1 xfs-ha1.company.com xfs-ha1
    190.0.2.3 stocks
    190.0.3.1 priv-xfs-ha1
    190.0.2.2 xfs-ha2.company.com xfs-ha2
    190.0.2.4 bonds
    190.0.3.2 priv-xfs-ha2
    

  2. Add all of the IP addresses from step 1 to /etc/hosts on the other node in the cluster.

  3. For IP addresses, IP names, and IP aliases that you did not add to /etc/hosts on the nodes, verify that they are in the NIS database by entering this command for each address:

    # ypmatch address hosts
    190.0.2.1 xfs-ha1.company.com xfs-ha1
    

    address is an IP address, IP name, or IP alias. If ypmatch reports that address doesn't match, it must be added to the NIS database.

  4. On one node, add that node's public and private interfaces and their fixed IP addresses to the file /etc/config/netif.options (high availability IP addresses are not added to the netif.options file).

    For the example in Figure 3-1, the public interface name and IP address lines are:

    if1name=ec0
    if1addr=$HOSTNAME
    

    $HOSTNAME is an alias for an IP address that appears in /etc/hosts.

    If there are additional public interfaces, their interface names and IP addresses appear on lines like these:

    if2name=
    if2addr=
    

    In the example, the private interface name and IP address are:

    if3name=ec3
    if3addr=priv-$HOSTNAME
    

    The private interface IP address in this example, priv-$HOSTNAME, is an alias for an IP address that appears in /etc/hosts.

  5. If there are more than eight interfaces on the node, change the value of if_num to the number of interfaces. For less than eight interfaces (as in the example in Figure 3-1) the line looks like this:

    if_num=8
    

  6. Repeat steps 4 and 5 on the other node.

  7. Edit the file /etc/config/routed.options on each node so that the routes are not shown over the private network (routing is turned off). The content of /etc/config/routed.options should be:

    -h -q
    

    These options are required for IRIS FailSafe to function correctly.

  8. Verify that IRIS FailSafe is chkconfig'd off on each node:

    # chkconfig 
            Flag                 State
            ====                 =====
            ...
            failsafe             off
            ...
    

    If failsafe is on on either node, enter this command on that node:

    # chkconfig failsafe off 
    

  9. Reboot both nodes to put the network configuration into effect.

  10. To configure your e-mail interface so that you can receive notification of cluster transitions, set up an e-mail alias on each node that includes at least one user outside the IRIS FailSafe cluster and an alias on the other node that can direct notification to an outside user. For example, in /usr/lib/aliases on each node, add

    fsafe_admin:outside,outside@xfs-ha1.company.com 
    outside:operations@console.company.com
    

  11. If the nodes use NIS (yp is chkconfig'ed on) or the BIND domain name server (DNS), switching to local name resolution is recommended. Create or modify the file /etc/resolv.conf so that local is listed first for the hostresorder keyword (the order of nis and bind is up to you):

    hostresorder local nis bind 
    

  12. If FDDI is being used, finish configuring the new FDDI station, as explained in Chapter 2 of the FDDIXpress Administration Guide. If you are familiar with the procedures, follow the section “Quick and Easy Configuration Instructions” in that chapter. Verify the FDDI connection as explained in Chapter 2 of the FDDIXpress Administration Guide.

Configuring the Serial Port

The getty process for the tty ports to which the reset serial cables are connected must be turned off. Perform these steps on each node:

  1. Determine which port is used for the reset serial line (see the section “Serial Port Configuration” in Chapter 2).

  2. Open the file /etc/inittab for editing.

  3. Find the line for the port by looking at the comments on the right for the port number from step 1.

  4. Change the third field of this line to off, for example:

    t2:23:off:/sbin/getty -N ttyd2 co_9600          # port 2
    

  5. Save the file.

  6. Enter these commands to make the change take effect:

    # killall getty
    # init q
    

Configuring NFS Filesystems

Follow the procedure below to perform the NFS configuration for the filesystems to be failed over and for the status monitor statd. Note that no entries in /etc/exports are required for these filesystems; IRIS FailSafe software exports NFS filesystems.

  1. Create or identify the filesystems to be failed over. They must follow the guidelines in the section “Planning Filesystems” in Chapter 2.

  2. On each node that exports filesystems, create the statmon directory on any one of the exported filesystems on a shared disk. The name of the directory must be statmon.

  3. For nodes that are running IRIX 5.3, skip the remaining steps in this procedure; they apply only to nodes that are running IRIX 6.2.

  4. On one node, open the file /etc/config/statd.options for editing (it may be new).

  5. Put -h on the first line of the file:

    -h 
    

  6. Close the file.

  7. Set the owner, group, and mode of the file, if you just created it:

    # chown root.sys /etc/config/statd.options
    # chmod 644 /etc/config/statd.options
    

  8. Repeat steps 4 through 7 on the other node.

Configuring a Netscape Server

To configure a Netscape Communications or Commerce Server, follow these steps:

  1. Because Netscape server installation requires that the interface be accessible from a Netscape browser, ifconfig the interface to the public network up by entering this command:

    # /usr/etc/ifconfig interface alias ip-address netmask netmask
    

    interface is the interface to be used access the server, ip-address is a high availability IP address for the interface, and netmask is the netmask of the IP address.

  2. To install the first Web server (stocks), enter

    # cd /usr/netscape/httpd/install
    # ./ns-setup
    

  3. Start the Netscape browser on a workstation and open the Netscape server's configuration page (see the output of the ns-setup command for the URL).

  4. Click the Server Config button and enter information according to the prompts. An example of the server information is as follows:

    • name of the server, for example stocks.company.com

    • IP address of the server, for example 190.0.2.3, if this is the only IP address that this server responds to (if it responds to any request, don't specify the IP address)

    • accessible on port 80, the default port for the Communications server, or port 443, the default port for the Commerce server

      Check /etc/services to make sure the port you want is not already in use. If you choose the default port, the URL to your home page will be http://servername.domainname. If you choose a different port, the URL to your home page will be http://servername.domainname:portnumber.

      To configure multiple Web servers, use the same IP address and different port numbers or different IP addresses and different port numbers.

    • installed in the directory /usr/ns-home

    • errors recorded to a file in the server root

  5. Click the Document Config button and enter information according to the prompts. An example of the information is as follows:

    • server looks for documents in /usr/ns-home/stocks_root (or use a symbolic link to a directory on a filesystem on a shared disk)

    • server looks for the documents index.html and home.html in directories

  6. Click the Admin Config button and enter information according to the prompts. Exit the page.

  7. Copy the contents of the server's root (/usr/ns-home/httpd-80.190.2.3) and document root (/usr/ns-home/stocks_root) to a filesystem on a shared disk.

  8. Replace the original directory with symbolic links to the directories on the shared disk.

Configuring IRIS FailSafe On

To configure IRIS FailSafe so that it starts up on a node each time it is rebooted, enter this command on the node:

# chkconfig failsafe on 


Note: During the testing described in Chapter 5, “Testing IRIS FailSafe Configuration,” IRIS FailSafe should be chkconfig'd off.