IBM RackSwitch G8000, Application Manual

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RackSwitch G8000: Application Guide
Transmit and Receive Control
The G8000 can also be configured to transmit or receive LLDP information on a
port-by-port basis. By default, when LLDP is globally enabled on the switch, G8000
ports transmit and receive LLDP information (see the
tx_rx
option in the following
example). To change the LLDP transmit and receive state, the following commands
are available:
To view the LLDP transmit and receive status, use the following commands:
LLDP Transmit Features
Numerous LLDP transmit options are available, including scheduled and minimum
transmit interval, expiration on remote systems, SNMP trap notification, and the
types of information permitted to be shared.
Scheduled Interval
The G8000 can be configured to transmit LLDP information to neighboring devices
once each 5 to 32768 seconds. The scheduled interval is global; the same interval
value applies to all LLDP transmit-enabled ports. However, to help balance LLDP
transmissions and keep them from being sent simultaneously on all ports, each port
maintains its own interval clock, based on its own initialization or reset time. This
allows switch-wide LLDP transmissions to be spread out over time, though
individual ports comply with the configured interval.
The global transmit interval can be configured using the following command:
where interval is the number of seconds between LLDP transmissions. The range is
5 to 32768. The default is 30 seconds.
Minimum Interval
In addition to sending LLDP information at scheduled intervals, LLDP information is
also sent when the G8000 detects relevant changes to its configuration or status
(such as when ports are enabled or disabled). To prevent the G8000 from sending
multiple LLDP packets in rapid succession when port status is in flux, a transmit
delay timer can be configured.
The transmit delay timer represents the minimum time permitted between
successive LLDP transmissions on a port. Any interval-driven or change-driven
updates will be consolidated until the configured transmit delay expires.
RS G8000(config)#
interface port 1
(Select a switch port)
RS G8000(config-if)#
lldp admin-status tx_rx
(Transmit and receive LLDP)
RS G8000(config-if)#
lldp admin-status tx_only
(Only transmit LLDP)
RS G8000(config-if)#
lldp admin-status rx_only
(Only receive LLDP)
RS G8000(config-if)#
no lldp admin-status
(Do not participate in LLDP)
RS G8000(config-if)#
exit
(Exit port mode)
RS G8000(config)#
show lldp port
(status of all ports)
RS G8000(config)#
show interface port
<n>
lldp
(status of selected port)
RS G8000(config)#
lldp refresh-interval
<interval>