VCS : Configure /etc/llttab

The /etc/llttab file must specify the system’s ID number (or its node name), its cluster ID, and the network links that correspond to the system. In addition, the file can contain other directives. Refer also to the sample llttab file in /opt/VRTSllt.

Run the dladm show-dev command to query all NICs.

Use vi or another editor to create the file /etc/lltab that contains the entries that resemble the following:

  • For SPARC:
        set-node galaxy
        set-cluster 2
        link qfe0 qfe:0 - ether - -
        link qfe1 qfe:1 - ether - -
  • For x64:
        set-node galaxy
        set-cluster 2
        link e1000g0 /dev/e1000g:0 - ether - -
        link e1000g1 /dev/e1000g:1 - ether - -

The first line must identify the system where the file exists. In the example, the value for set-node can be: galaxy, 0, or the file name /etc/nodename. The file needs to contain the name of the system (galaxy in this example). The next two lines, beginning with the link command, identify the two private network cards that the LLT protocol uses. The order of directives must be the same as in the sample llttab file in /opt/VRTSllt

LLT directives for a manual installation

Table: LLT directives

Directive Description
set-node Assigns the system ID or symbolic name. The system ID number must be unique for each system in the cluster, and must be in the range 0-31. The symbolic name corresponds to the system ID, which is in /etc/llthosts file.

Note that LLT fails to operate if any systems share the same ID.

link Attaches LLT to a network interface. At least one link is required, and up to eight are supported. The first argument to link is a user-defined tag shown in the lltstat(1M) output to identify the link. It may also be used in llttab to set optional static MAC addresses.

The second argument to link is the device name of the network interface. Its format is device_name:device_instance_number.

The remaining four arguments to link are defaults; these arguments should be modified only in advanced configurations. There should be one link directive for each network interface. LLT uses an unregistered Ethernet SAP of 0xCAFE. If the SAP is unacceptable, refer to the llttab(4) manual page for information on how to customize SAP. Note that IP addresses do not need to be assigned to the network device; LLT does not use IP addresses.

set-cluster Assigns a unique cluster number. Use this directive when more than one cluster is configured on the same physical network connection. LLT uses a default cluster number of zero.
link-lowpri Use this directive in place of link for public network interfaces. This directive prevents VCS communication on the public network until the network is the last link, and reduces the rate of heartbeat broadcasts. Note that LLT distributes network traffic evenly across all available network connections. In addition to enabling VCS communication, it broadcasts heartbeats to monitor each network connection



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1 Response

  1. September 18, 2015

    […] Read – VCS for Beginners – Configure /etc/llttab […]

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