3Com 5500 SI - Switch - Stackable, Configuration Manual

Page: 93 / 686

DLDP Configuration 93
Precautions During DLDP
Configuration
It is recommended that the following precautions be taken during DLDP
configuration:
n
DLDP works only when the link is up.
n
To ensure unidirectional links can be detected, you should make sure: DLDP is
enabled on both ends, and the time interval for sending advertisement packets,
authentication mode and password are set consistent on both ends.
n
You can adjust the time interval for sending advertisement packets in different
network circumstances, so that DLDP can respond rapidly to link failure. The time
interval should be shorter than one-third of the STP convergence time, which is
generally 30 seconds. If too long time interval is set, an STP loop may occur before
DLDP shut down unidirectional links. On the contrary, if too short time interval is
set, network traffic increases, and port bandwidth is reduced.
n
DLDP does not process any LACP event, and treats each link in the aggregation
group as independent.
For the configuration of distributed products, note that:
n
During hot plugging, if the interface board you insert has the same type as that
you have removed, DLDP restores working automatically.
n
After the SRPU board switchover, the standby board takes over unidirectional link
detection. In this case, the DLDP parameters do not change and DLDP checks every
port again for unidirectional links.
For the configuration of the products supporting expandable resilient networking
(XRN), note that:
n
DLDP supports XRN; its processing is fully distributed. In XRN, port management is
distributed to each port. Each unit completes only the DLDP tasks for its ports.
DLDP commands executed on a port take effect only on the unit where the port is
located.
n
The global DLDP configuration must be consistent on all units. The global DLDP
configuration commands take effect on all the units in the XRN.
n
Stack ports do not support DLDP.
DLDP Configuration
Table 77 describes the DLDP basic configuration tasks:
Table 77
DLDP configuration tasks
Operation Command Description
Enter system view system-view -
Enable DLDP Enable DLDP globally dldp enable Required, by default,
DLDP is disabled
Enable
DLDP on a
port Enter
Ethernet
port view interface { interface-type
interface-number |
interface_name
}
Enable
DLDP on a
port dldp enable
Set the authentication mode and
password dldp authentication-mode
{ none | simple password |
md5 password }
Optional, by default, the
authentication mode is
none
Set the time interval for sending DLDP
packets dldp interval integer Optional, by default, the
time interval is 10
seconds.