Brocade Unified IP MIB Reference (Supporting FastIron Release 07.5.00) - Manual (Page 267)

Unified IP MIB Reference 239
53-1002549-02
Chapter
14
Trace route group
In this chapter
• Trace route group. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 239
• General trace route group. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 239
• Trace route result table . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 240
• IP forwarding cache table . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 241
• IP AS-Path access list table. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 242
• IP community list table . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 243
• IP prefix list table . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 244
• IP AS-Path access list string table . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 246
• IP community list string table . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 246
Trace route group
This group uses the following method to detect routes used to reach a destination address.
1. The originating Layer 3 Switch sends a probe packet (a UDP packet) to the destination address
with a time-to-live (TTL) value of 1.
2. The first Layer 3 Switch that receives this packet decrements the TTL, then drops the packet
and returns a ICMP packet to the originator.
3. The originating Layer 3 Switch records the route in the “snRtIpTraceRouteResultTable” .
4. The originating Layer 3 Switch sends a probe packet (a UDP packet) to the destination address
with a TTL value of 2.
5. The second Layer 3 Switch that receives this packet decrements the TTL, then drops the
packet and returns an ICMP packet to the originator.
6. The originating Layer 3 Switch records the route in “snRtIpTraceRouteResultTable” .
This procedure is repeated until the destination is reached or the maximum TTL is reached.
General trace route group
The following objects define the trace route probe packet.