LLT provides kernel-to-kernel communications and monitors network communications. The LLT files /etc/llthosts
and /etc/llttab
can be configured to set system IDs within a cluster, set cluster IDs for multiple clusters, and tune network parameters such as heartbeat frequency. LLT is implemented so that events such as state changes are reflected quickly, which in turn enables fast responses.
As with GAB, LLT is configured automatically when you run the VCS installation script. The file /etc/llttab
contains information derived from what you input during installation. You may also have to reconfigure LLT when you add a node to a cluster.
See the llttab
(4) manual page.