enable elsm ports
ExtremeWare XOS 11.5 supports only the Summit X450 family of switches and the BlackDiamond 8800 series switch.
ExtremeWare XOS 11.5 Command Reference Guide
641
enable elsm ports
enable elsm ports <portlist>
Description
Enables the ELSM protocol for the specified ports.
Syntax Description
Default
The default is disabled.
Usage Guidelines
The ELSM protocol allows you to detect CPU and remote link failures in the network. ELSM operates
on a point-to-point basis; you only configure ELSM on the ports that connect to other devices within the
network, but you must configure ELSM on both sides of the peer connections.
The Layer 2 connection between the ports determines the peer. You can have a direct connection
between the peers or hubs that separate peer ports. In the first instance, the peers are also considered
neighbors. In the second instance, the peer is not considered a neighbor.
An Extreme Networks device with ELSM enabled detects CPU and remote link failures by exchanging
hello messages between two ELSM peers. If ELSM detects a failure, the ELSM-enabled port responds by
blocking traffic on that port. For example, if a peer stops receiving messages from its peer, ELSM brings
down that connection by blocking all incoming and outgoing data traffic on the port and notifying
applications that the link is down.
Configuring and enabling ELSM on Extreme Networks devices running ExtremeWare XOS is backward
compatible with Extreme Networks devices running ExtremeWare.
When you enable ELSM on a port, ELSM immediately blocks the port and it enters the Down state.
When the port detects an ELSM-enabled peer, the peer ports exchange ELSM hello messages. At this
point, the ports enter the transitional Down-Wait state. If the port receives Hello+ messages from its
peer and does not detect a problem, the peers enter the Up state. If a peer detects a problem or there is
no peer port configured, the port enters the Down state.
For more information about the types of ELSM hello messages, see the
configure elsm ports
hellotime
command.
NOTE
ELSM and mirroring are mutually exclusive. You can enable either ELSM, or mirroring, but not both.
portlist
Specifies the port or ports for which ELSM should be enabled.
