CCNA: General/Static Routing

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General Routing commands

How to set a static route:

   Router(config)#ip route [destination_network] [mask] [interfaceName] [cost]
   Router(config)#ip route fa0/0 1

For ipv6:

   R1(config)#ipv6 route [ipv6-prefix/prefix-length] [next-hop-address | [interface][distance | multicast | tag | unicast]

   R1(config)#ipv6 route 3FFF:1234:ABCD:0001::/64 Fa0/0 unicast # to subnet 3FFF:1234:ABCD:0001::/64, will forward traffic out of the FastEthernet0/0 interface. This route will be used only for Unicast traffic.

   R1(config)#ipv6 route 3FFF:1234:ABCD:0002::/64 Se0/0 FE80::2222 multicast # to subnet 3FFF:1234:ABCD:0002::/64, will forward packets to that subnet out of Serial0/0 using the Link- Local address of the next-hop router as the IPv6 next-hop address. This route will be used only for Multicast traffic.

   R1(config)#ipv6 route ::/0 Serial0/1 FE80::3333 # a default route pointing out of interface Serial0/1 is also configured. This default route will forward packets to unknown IPv6 destinations via Serial0/1 using the Link-Local address of the next-hop router as the IPv6 next-hop address.

To Create a default gateway (switch):

   Switch(config)#ip default-gateway only do this if ip routing is disabled like on a switch.

To set the default gateway (router):

   # From my understanding, this command is issued when you use dynamic protocols that want to choose the route dynamically instead of a static catch-all route.
   Router(config)#ip default-network
   Router(config)#ip default-network

To create a passive interface:

  • This is an important command. We use it often to configure dynamic protocols to only work on one side of a router while keeping the ports you specify with this command free from routing protocols being advertised or passed over. Think about it, end devices do not need to see OSPF or EIGRP packets – so we set this up!
   Router(config)#passive-interface [interface number]
   Router(config)#passive-interface fa0/2


   R2#ping source repeat 10 # see protocols section to determine symbol meanings.

Show Commands:

   show ip route
   show ip route
   show ip protocols # shows if dynamic routing protocols have been enabled
   show ipv6 route static
   show ipv6 static [prefix] [detail] ex: show ipv6 static 3FFF:1234:ABCD:1::/64 detail

Cisco Administrative Distance

Route Source – Default Distance Values

Connected interface – 0
Static route – 1
EIGRP summary route -5
External BGP – 20
Internal EIGRP – 90
IGRP – 100
OSPF – 110
IS-IS – 115
RIP – 120
EGP – 140
ODR – 160
External EIGRP – 170
Internal BGP – 200
Unknown 255*