About the LLT and GAB configuration files
Low Latency Transport (LLT) and Group Membership and Atomic Broadcast (GAB) are VCS communication services. LLT requires /etc/llthosts and /etc/llttab files. GAB requires /etc/gabtab file.
The information that these LLT and GAB configuration files contain is as follows:
The /etc/llthosts file
The file llthosts is a database that contains one entry per system. This file links the LLT system ID (in the first column) with the LLT host name. This file is identical on each node in the cluster.
For example, the file /etc/llthosts contains the entries that resemble:
The /etc/llttab file
The file llttab contains the information that is derived during installation and used by the utility lltconfig(1M). After installation, this file lists the private network links that correspond to the specific system.
link en1 /dev/dlpi/en:1 - ether - -
link en2 /dev/dlpi/en:2 - ether - -
For example, the file /etc/llttab contains the entries that resemble:
link lan1 /dev/lan:1 - ether - -
link lan2 /dev/lan:2 - ether - -
The first line identifies the system. The second line identifies the cluster (that is, the cluster ID you entered during installation). The next two lines begin with the link command. These lines identify the two network cards that the LLT protocol uses.
Refer to the llttab(4) manual page for details about how the LLT configuration may be modified. The manual page describes the ordering of the directives in the llttab file.
The /etc/gabtab file
After you install VCS, the file /etc/gabtab contains a gabconfig(1) command that configures the GAB driver for use.
The file /etc/gabtab contains a line that resembles:
/sbin/gabconfig -c -nN
The -c option configures the driver for use. The -nN specifies that the cluster is not formed until at least N nodes are ready to form the cluster. By default, N is the number of nodes in the cluster.
The use of the -c -x option for /sbin/gabconfig is not recommended.