cancel
Showing results for 
Search instead for 
Did you mean: 
cancel
484
Views
0
Helpful
5
Replies

sh run out put explanation

saidfrh
Level 1
Level 1

What do the following from output of sh run refer to?

no service pad

service tcp-keepalives-in

service tcp-keepalives-out

1 Accepted Solution

Accepted Solutions

Yes if you're not using X.25, disable PAD.

service tcp-keepalives-in is to the router management plane, not traffic going through the router. Here's a common example; You telnet into a router and do some work. Instead of logging off the router you just close your terminal application. The router thinks your still connected and is waiting for input. If you do that enough times, you'll use up all your VTY lines and you won't be able to access the router via telnet. With service tcp-keepalives-in the router will timeout the session after inactivity ensuring you always have a VTY line available.

Hope that helps

View solution in original post

5 Replies 5

Collin Clark
VIP Alumni
VIP Alumni

no service PAD shuts off PAD.

A packet assembler/disassembler, abbreviated PAD is a communications device which provides multiple asynchronous terminal connectivity to an X.25 (packet-switching) network or host computer. It collects data from a group of terminals and places the data into X.25 packets (assembly). A PAD also does the reverse, it takes data packets from packet-switching network or host computer and returns them into a character stream that can be sent to the terminals (disassembly).

service tcp-keepalives-in

To generate keepalive packets on idle incoming network connections (initiated by the remote host), use the service tcp-keepalives-in command in global configuration mode.

service tcp-keepalives-out

To generate keepalive packets on idle outgoing network connections (initiated by a user), use the service tcp-keepalives-out command in global configuration mode.

Hope that helps.

So, if we are not using X.25, the above service should be disabled.

service tcp-keepalives-in, does this refer to keeping the TCP session open, while reciving syn, ack...TCP protocol activities?

Yes if you're not using X.25, disable PAD.

service tcp-keepalives-in is to the router management plane, not traffic going through the router. Here's a common example; You telnet into a router and do some work. Instead of logging off the router you just close your terminal application. The router thinks your still connected and is waiting for input. If you do that enough times, you'll use up all your VTY lines and you won't be able to access the router via telnet. With service tcp-keepalives-in the router will timeout the session after inactivity ensuring you always have a VTY line available.

Hope that helps

On another note, what does no ip source-route refer to?

IP source routing allows the sender of an IP packet to control the route that packet will take to reach the destination endpoint. By default, IP source routing is disabled on the routers and should only be enabled if your network needs call for it.

Getting Started

Find answers to your questions by entering keywords or phrases in the Search bar above. New here? Use these resources to familiarize yourself with the community:

Innovations in Cisco Full Stack Observability - A new webinar from Cisco