cancel
Showing results for 
Search instead for 
Did you mean: 
cancel
Announcements
Join Customer Connection to register!
1600
Views
0
Helpful
4
Replies
adil.nasser3
Beginner

Extended Ping - How do you increase hops

Hello,

It appears that the extended ping function in a cisco router or switch has a limit of 9 hops.  Is there any way to increase this?

CH-3560-6#ping

Protocol [ip]:

Target IP address: 10.150.40.60

Repeat count [5]:

Datagram size [100]:

Timeout in seconds [2]:

Extended commands [n]: y

Source address or interface: 10.181.4.6

Type of service [0]:

Set DF bit in IP header? [no]:

Validate reply data? [no]:

Data pattern [0xABCD]:

Loose, Strict, Record, Timestamp, Verbose[none]: R

Number of hops [ 9 ]: 10

Invalid Number of Hops

Loose, Strict, Record, Timestamp, Verbose[none]: R

Number of hops [ 9 ]: 12

Invalid Number of Hops

Loose, Strict, Record, Timestamp, Verbose[none]: R

Number of hops [ 9 ]:

Loose, Strict, Record, Timestamp, Verbose[RV]:

Sweep range of sizes [n]:

Type escape sequence to abort.

Sending 5, 100-byte ICMP Echos to 10.150.40.60, timeout is 2 seconds:

Packet sent with a source address of 10.181.4.6

1 ACCEPTED SOLUTION

Accepted Solutions
milan.kulik
Advocate

Hi,

it's not the Extended Ping, just the Record option.

But no chance to increase, I'm afraid.

And not only due to Cisco IOS implementation.

RFC 1812 (https://tools.ietf.org/html/rfc1812#section-4.3.3.6 ) says:

" If a Record Route and/or Timestamp option is received in an ICMP Echo

   Request, this option (these options) SHOULD be updated to include the

   current router and included in the IP header of the Echo Reply

   message, without truncation.  Thus, the recorded route will be for

   the entire round trip."

If you look at the IP header structure (http://en.wikipedia.org/wiki/IPv4#Header ), you will see there is only space for 9 IP addresses left in the IP header Options field.

HTH,

Milan

Message was edited by: MILAN KULIK

View solution in original post

4 REPLIES 4
Takashi Higashimura
Cisco Employee

Hi,

There is no way to increase that value.

And also please check following past-discussion.

Giuseppe Larosa
Hall of Fame Master

Hello Adil,

the extended ping number of hops is limited to 9 router hops.

within 9 router hops the extended ping provides the path for the transmit and return path

You can use traceroute from A to B and from B to A to find out the paths in the two directions.

Hope to help

Giuseppe

milan.kulik
Advocate

Hi,

it's not the Extended Ping, just the Record option.

But no chance to increase, I'm afraid.

And not only due to Cisco IOS implementation.

RFC 1812 (https://tools.ietf.org/html/rfc1812#section-4.3.3.6 ) says:

" If a Record Route and/or Timestamp option is received in an ICMP Echo

   Request, this option (these options) SHOULD be updated to include the

   current router and included in the IP header of the Echo Reply

   message, without truncation.  Thus, the recorded route will be for

   the entire round trip."

If you look at the IP header structure (http://en.wikipedia.org/wiki/IPv4#Header ), you will see there is only space for 9 IP addresses left in the IP header Options field.

HTH,

Milan

Message was edited by: MILAN KULIK

View solution in original post

Hello Milan,

very good finding it explains the root cause of the limitation with the record option in extended ping.

Best Regards

Giuseppe