Next Hop rechability issue with Cisco/Juniper/Huawei Gears
Next Hop rechability issue with Cisco/Juniper/Huawei Gears:
Similar threads:
http://newsgroups.derkeiler.com/Archive/Comp/comp.dcom.sys.cisco/2008-03/msg00009.html
With reference to BFD:
http://puck.nether.net/pipermail/cisco-nsp/2008-January/046785.html
Do we recall these?
1. Even before router is configured with static routes, it has a routing table.
2. Each routed protocol (like IP or IPX) maintains its own routing table.
3. Before any static (or dynamic) routes exist, a routing table will show entries for only
directly connected networks.
4. The complete syntax of the “ip route” command is:
ip route [destination network] [mask] [next hop address OR exit interface]
[administrative distance] [permanent]
5. Directly connected network is Coded with “C” while Static Routes are Coded as “S” in
“show ip route” command’s output.
6. AD for Directly Connected network is “0″ where as for Static Route it’s “1″.
7. When the primary route is a static route, the primary interface line protocol must go
down for the floating static route to be used.
Reference:
http://www.cisco.com/en/US/tech/tk801/tk133/technologies_tech_note09186a008009457d.shtml#floating_sequence
Solution:
8. Enabling next hop rechability information in JUNOS: (RTR)
http://www.juniper.net/techpubs/software/junos/junos92/swconfig-routing/enabling-next-hop-reachability-information.html
Configuring Bidirectional Forwarding Detection in JUNOS:
http://www.juniper.net/techpubs/software/junos/junos73/swconfig73-routing/html/routing-tables-config22.html11.
9. Configuring BFD Support for Static Routing:
http://www.cisco.com/en/US/docs/ios/iproute/configuration/guide/irp_bfd_ps6441_TSD_Products_Configuration_Guide_Chapter.html#wp1055179
10. Limitations: IOS, Platfor and Protocol:
For Cisco IOS Release 12.2(33)SRC, and Cisco IOS XE Release 2.1, BFD is supported for static routing.
11. Use dynamic protocols, they were invented to solve this issue.
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