Command IP fast switching on the same interface is disabled

[mahesh18]

Hi All,

My routers interface fa0/0  connects to cable modem

sh ip int fa0/0

FastEthernet0/0 is up, line protocol is up

  Internet address is x.x.x.x/22

  Broadcast address is 255.255.255.255

  Address determined by DHCP

  MTU is 1500 bytes

  Helper address is not set

  Directed broadcast forwarding is disabled

  Outgoing access list is 110

  Inbound  access list is 102

  Proxy ARP is enabled

  Local Proxy ARP is disabled

  Security level is default

  Split horizon is enabled

  ICMP redirects are never sent

  ICMP unreachables are never sent

  ICMP mask replies are never sent

  IP fast switching is enabled

  IP fast switching on the same interface is disabled **************************************************************

  IP Flow switching is disabled

  IP CEF switching is enabled

  IP CEF Feature Fast switching turbo vector

  IP multicast fast switching is enabled

  IP multicast distributed fast switching is disabled

  IP route-cache flags are Fast, CEF

  Router Discovery is disabled

  IP output packet accounting is disabled

  IP access violation accounting is disabled

  TCP/IP header compression is disabled

  RTP/IP header compression is disabled

  Policy routing is disabled

  Network address translation is enabled, interface in domain outside

  BGP Policy Mapping is disabled

  WCCP Redirect outbound is disabled

  WCCP Redirect inbound is disabled

  WCCP Redirect exclude is disabled

IT has cef and fast switching enabled.

My question is should i enable it or not   ---   IP fast switching on the same interface is disabled??

Will it make router performance better?

Thanks

Mahesh

[Joseph W. Doherty · Accepted solution]

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Posting

Unlikely you need it.  Same interface fast switching applies to where the ingress and egress interface are one and the same.

[mahesh18]

Hi JosephDoherty,

Thanks for reply.

So in my  case fa0/0 connects to the Cable modem and interface fa0/1 connects to LAN.

So this shows  my ingress and egress interfaces are not same right??

Mahesh

[Richard Burts · Accepted solution]

Mahesh

Yes in your case Fa0/0 connecting to Cable modem and Fa0/1 connecting to LAN are definitely not same ingress and egress. Where it might come in handy is if you were doing router on a stick where traffic from a client would come in Fa0/1 and then be forwarded back out Fa0/1 to get to the destination then you would benefit from fast switching same interface.

HTH

Rick

[mahesh18]

Hi Rick,

Many thanks again for detail explanation.

Regards

Mahesh