From: Huan Pham (Huan.Pham@peopletelecom.com.au)
Date: Thu Nov 06 2008 - 03:36:27 ARST
Local Policy should be able do what you need:
route-map SET_DF permit 10
set ip df 1
ip local policy route-map SET_DF
I tested this with a simple topology:
155.1.13.0/24 155.1.23.0/24
R1 ---------------- R3 ----------------- R2
Default MTU MTU = 200
Rack1R1#sh run | b sla
ip sla monitor 1
type echo protocol ipIcmpEcho 155.1.23.2
request-data-size 1000
frequency 10
ip sla monitor schedule 1 life forever start-time now
Pings with default DF=0 get through:
------------------------------------
Rack1R1#ping 155.1.23.2 size 1000
Type escape sequence to abort.
Sending 5, 1000-byte ICMP Echos to 155.1.23.2, timeout is 2 seconds:
!!!!!
Success rate is 100 percent (5/5), round-trip min/avg/max = 444/444/444
ms
Pings with DF do not get through:
----------------------------------
Rack1R1#ping
Protocol [ip]:
Target IP address: 155.1.23.2
Repeat count [5]:
Datagram size [100]: 1000
Timeout in seconds [2]:
Extended commands [n]: y
Source address or interface:
Type of service [0]:
Set DF bit in IP header? [no]: yes
Validate reply data? [no]:
Data pattern [0xABCD]:
Loose, Strict, Record, Timestamp, Verbose[none]:
Sweep range of sizes [n]:
Type escape sequence to abort.
Sending 5, 1000-byte ICMP Echos to 155.1.23.2, timeout is 2 seconds:
Packet sent with the DF bit set
M.M.M
Success rate is 0 percent (0/5)
Rack1R1#
Before applying Local Policy to mark DF = 1, all SLA returns positive.
----------------------------------------------------------------------
Rack1R1#sh ip sla monitor statistics 1
Round trip time (RTT) Index 1
Latest RTT: 456 ms
Latest operation start time: *07:06:07.378 UTC Fri Mar 1 2002
Latest operation return code: OK
Number of successes: 58
Number of failures: 0
Operation time to live: Forever
Now I apply Local Policy to mark DF = 1, we start seeing losses.
----------------------------------------------------------------
Rack1R1#c
Enter configuration commands, one per line. End with CNTL/Z.
Rack1R1(config)#route-map SET_DF permit 10
Rack1R1(config-route-map)# set ip df 1
Rack1R1(config-route-map)#
Rack1R1(config-route-map)#ip local policy route-map SET_DF
Rack1R1(config)#
Rack1R1#sh ip sla monitor statistics 1
Round trip time (RTT) Index 1
Latest RTT: NoConnection/Busy/Timeout
Latest operation start time: *07:08:07.378 UTC Fri Mar 1 2002
Latest operation return code: Timeout
Number of successes: 68
Number of failures: 2
Operation time to live: Forever
-----Original Message-----
From: nobody@groupstudy.com [mailto:nobody@groupstudy.com] On Behalf Of
Bit Gossip
Sent: Thursday, 6 November 2008 7:55 AM
To: ccielab@groupstudy.com
Subject: TTL & DontFragment for IP-SLA
Experts,
it doesn't look like there is a possibility to set these two parameters
in the outgoing probes of IP-SLA type jitter. Any idea of how
alternatively I could set them?
Thanks,
Bit
Blogs and organic groups at http://www.ccie.net
This archive was generated by hypermail 2.1.4 : Mon Dec 01 2008 - 08:18:29 ARST