Friday, May 10, 2013

RIP v6 What you need to remember

1. Frame-Relay hub and spoke topology: disable the split-horizon, or use summarization or default route.

2. broadcast keyword when mapping DLCI so as to not breaking mcast propagation/replication/forwarding.




R5#sh run int s0/0/0
!
interface Serial0/0/0
 ip address 155.1.0.5 255.255.255.0
 ip rip advertise 10
 encapsulation frame-relay
 ipv6 address FE80::5 link-local
 ipv6 address 2001:1:0:1234::5/64
 ipv6 rip 1 enable
 frame-relay map ipv6 2001:1:0:1234::4 504
 frame-relay map ipv6 2001:1:0:1234::3 503
 frame-relay map ipv6 2001:1:0:1234::2 502
 frame-relay map ipv6 2001:1:0:1234::1 501
 frame-relay map ipv6 FE80::4 504 broadcast
 frame-relay map ipv6 FE80::3 503 broadcast
 frame-relay map ipv6 FE80::2 502 broadcast
 frame-relay map ipv6 FE80::1 501 broadcast
 frame-relay map ip 155.1.0.4 504 broadcast
 frame-relay map ip 155.1.0.3 503 broadcast
 frame-relay map ip 155.1.0.2 502 broadcast
 frame-relay map ip 155.1.0.1 501 broadcast
 no frame-relay inverse-arp
end


3. Note the bizarre behavior or the prefix-list cli for IPv6 :-(.
-  Need to put in the entire line, no ? or sub mode.
do show command won't execute from the config mode unless 'prefix-list' is spelled out.

R1(config)#ipv6 prefix-list ?
  sequence-number  Include/exclude sequence numbers in NVGEN

R1(config)#ipv6 prefix-list sequence-number ?
  <cr>

R1(config)#ipv6 prefix-list sequence-number
Prefix-list name is empty
R1(config)#
R1(config)#ipv6 prefix-list                
% Incomplete command.
 

R1(config)#ipv6 prefix-list sequence-number 10
                                            ^
% Invalid input detected at '^' marker.

R1(config)#ipv6 prefix-list MY_
R6L100 permit ::0/128
R1(config)#
R1(config)#do sh ipv6 prefix
sh ipv6 prefix
% Incomplete command.
 

R1(config)#exit
R1#sh ipv6 prefix-list
ipv6 prefix-list MY_
R6L100: 1 entries
   seq 5 permit ::/128
R1#

R1#sh ipv6 prefix- detail
Prefix-list with the last deletion/insertion: MY_R6L100
ipv6 prefix-list MY_R6L100:
   count: 2, range entries: 1, sequences: 5 - 10, refcount: 3
   seq 5 deny FC00:1:0:6::/64 (hit count: 4, refcount: 1)
   seq 10 permit ::/0 le 128 (hit count: 16, refcount: 1)
R1#


RIP what you need to remember

1.    The RIP process uses UDP port 520 
2.    The metric used by RIP is hop count, with 1 signifying a directly connected network of the advertising router and 16 signifying an unreachable network. 
3.    RIP sends periodic updates every 30 seconds  
4.    Default route can be advertised via: 
Static route 0.0.0.0, via redistribute static command.
default-information originate command advertises a default route even if a default route does not exist in the routing table. The route map must be standard access list.
ip default-network command provided the network address is a classfull network that router has a directly connected interface into that network AND the classfull network is in the local router’s routing table
5.    Unlike EIGRP the neighbor command under RIP process does not automatically suppress the sending of broadcast or multicast updates. The passive-interface command needed to get the same behavior/results. passive interface in RIP only stops the router sending updates out, it’ll still receive updates in from neighbors. If you have configured a static neighbor it’ll send unicast updates even if passive-interface has been configured.
6.    In RIP, route feedback may occur when generating summaries because RIP does not generate a route to Null0 like EIGRP, OSPF, and BGP. Possible solutions are static route to Null0, or distribute-list inbound filtering. 
7.    Supernet advertisement -advertising any network prefix less than its classfull major network- is not allowed via ip summary-address. Only one summary address can be configured for each classfull subnet. 
8.    The interface command ip rip triggered enables the router to send triggered updates only when there is a topology change. This command is only available on point-to-point serial links and must be configured on both ends of the link for it to work. 
9.   For secondary address on an interface disable ip split-horizon or no validate update source on the other/peer router. when connecting to non-Cisco devices you need to disable the holddown timer. timers basic 30 180 0 240
10.   IP split horizon checking is disabled by default for Frame Relay encapsulation to allow routing updates to go in and out of the same interface. An exception is the Enhanced Interior Gateway Routing Protocol (EIGRP) for which split horizon must be explicitly disabled.