HP 2910AL User Manual

Page 378

Advertising
background image

Configuring for Network Management Applications
LLDP (Link-Layer Discovery Protocol)

Syntax setmib lldpTxDelay.0 -i < 1 - 8192 >

Uses

setmib to change the minimum time (delay-interval) any

LLDP port will delay advertising successive LLDP
advertisements due to a change in LLDP MIB content. (Default:
2; Range: 1 - 8192)

Note:

The LLDP refresh-interval (transmit interval) must be

greater than or equal to (4

x delay-interval). The switch does

not allow increasing the delay interval to a value that conflicts
with this relationship. That is, the switch displays

Inconsistent

value if (4 x delay-interval) exceeds the current transmit
interval, and the command fails. Depending on the current
refresh-interval setting, it may be necessary to increase the
refresh-interval before using this command to increase the
delay-interval.

For example, to change the delay-interval from 2 seconds to 8 seconds when
the refresh-interval is at the default 30 seconds, you must first set the refresh-
interval to a minimum of 32 seconds (32 = 4 x 8).

Figure 14-19. Example of Changing the Transmit-Delay Interval

Attempt to change the transmit-delay
interval shows that the refresh-
interval is less than (4 x delay-interval).

Changes the refresh-interval to 32; that is:
32 = 4 x (desired transmit-delay interval)

Successfully changes the transmit-
delay interval to 8.

Changing the Reinitialization Delay Interval.

In the default

configuration, a port receiving a

disable command followed immediately by a

txonly, rxonly, or tx_rx command delays reinitializing for two seconds, during
which time LLDP operation remains disabled. If an active port is subjected to
frequent toggling between the LLDP disabled and enabled states, LLDP
advertisements are more frequently transmitted to the neighbor device. Also,
the neighbor table in the adjacent device will change more frequently, as it
deletes, then replaces LLDP data for the affected port which, in turn, generates
SNMP traps (if trap receivers and SNMP notification are configured). All of
this can unnecessarily increase network traffic. Extending the reinitialization­

14-50

Advertising