Operation Manual – IPv4 Routing
H3C S3610&S5510 Series Ethernet Switches
Chapter 4 IS-IS Configuration
4-12
Figure 4-9
L1/L2 LSP format
z
PDU Length: Total length of the PDU in bytes.
z
Remaining Lifetime: LSP remaining lifetime in seconds.
z
LSP ID: Consists of the system ID, the pseudonode ID (one byte) and the LSP
fragment number (one byte).
z
Sequence Number: LSP sequence number.
z
Checksum: LSP checksum.
z
P (Partition Repair): Only related with L2 LSP, indicates whether the router
supports partition repair.
z
ATT (Attachment): Generated by the L1/L1 router, only related with L1 LSP,
indicates that the router generating the LSP is connected with multiple areas.
z
OL (LSDB Overload): Indicates that the LSDB is not complete because the router
is running out of system resources. In this condition, other routers will not send
packets to the overloaded router, except packets destined to the networks directly
connected to the router. For example, in
, Router A uses Router B to
forward its packets to Router C in normal condition. Once other routers know the
OL field on Router B is set to 1, Router A will send packets to Router C via Router
D and Router E, but still send to Router B packets destined to the network directly
connected to Router B.