H3C Technologies H3C S3100 Series Switches - Manual (Page 157)

Operation Manual – DLDP
H3C S3100-52P Ethernet Switch Chapter 1 DLDP Configuration
1-3
Status Description
Probe
DHCP sends packets to check whether the link is a unidirectional.
It enables the probe sending timer and an echo waiting timer for
each target neighbor.
Disable
DLDP detects a unidirectional link, or finds (in enhanced mode)
that a neighbor disappears. In this case, DLDP does not receive or
send DLDP packets.
Delaydown
When a device in the active, advertisement, or probe DLDP state
receives a port down message, it does not removes the
corresponding neighbor immediately, neither does it changes to
the inactive state. Instead, it changes to the delaydown state first.
When a device changes to the delaydown state, the related DLDP
neighbor information remains, and the Delaydown timer is
triggered.
II. DLDP timers
DLDP works with the following timers:
Table 1-2
DLDP timers
Timer Description
Advertisement
sending timer
Interval between sending advertisement packets, which can be
configured on a command line interface.
By default, the timer length is 10 seconds.
Probe sending
timer
The interval is 0.5 seconds. In the probe state, DLDP sends two
probe packets every second.
Echo waiting
timer
It is enabled when DLDP enters the probe state. The echo waiting
timer length is 10 seconds.
If no echo packet is received from the neighbor when the Echo
waiting timer expires, the state of the local end is set to
unidirectional link (one-way audio) and the state machine turns
into the disable state. DLDP outputs log and tracking information,
sends flush packets. Depending on the user-defined DLDP down
mode, DLDP disables the local port automatically or prompts you
to disable the port manually. At the same time, DLDP deletes the
neighbor entry.