Hi, The simplest way would be to ping your host from the dhcp server with packet size of just above and just below your desired mtu size with the df-bit set
Eg. To test for an MTU of 1500 # ping -s 1472 192.168.1.50 -M do PING 192.168.1.50 (192.168.1.50) 1472(1500) bytes of data. 1480 bytes from 192.168.1.50: icmp_req=1 ttl=64 time=0.362 ms 1480 bytes from 192.168.1.50: icmp_req=2 ttl=64 time=0.293 ms # ping -s 1473 192.168.1.50 -M do PING 192.168.1.50 (192.168.1.50) 1473(1501) bytes of data. >From 192.168.1.1 icmp_seq=1 Frag needed and DF set (mtu = 1500) >From 192.168.1.1 icmp_seq=1 Frag needed and DF set (mtu = 1500) HTH Paul -----Original Message----- From: [email protected] [mailto:[email protected]] On Behalf Of M K Sent: 13 November 2012 12:17 To: [email protected] Subject: [c-nsp] MTU Testing Hi , am trying to configure my linux DHCP server to send the MTU size (Option 26) in the DHCP server Now , what are the best ways to test if the value sent via the offer is correct and as configured? Thanks _______________________________________________ cisco-nsp mailing list [email protected] https://puck.nether.net/mailman/listinfo/cisco-nsp archive at http://puck.nether.net/pipermail/cisco-nsp/ --------------------------------------- -- ********************************************* Confidentiality: The contents of this e-mail and any attachments transmitted with it are intended to be confidential to the intended recipient; and may be privileged or otherwise protected from disclosure. If you are not an intended recipient of this e-mail, do not duplicate or redistribute it by any means. Please delete it and any attachments and notify the sender that you have received it in error. This e-mail is sent by a William Hill PLC group company. The William Hill group companies include, among others, William Hill PLC (registered number 4212563), William Hill Organization Limited (registered number 278208), William Hill US HoldCo Inc, WHG (International) Limited (registered number 99191) and WHG Trading Limited (registered number 101439). Each of William Hill PLC, William Hill Organization Limited is registered in England and Wales and has its registered office at Greenside Hou! se, 50 Station Road, Wood Green, London N22 7TP. William Hill U.S. HoldCo, Inc. is 160 Greentree Drive, Suite 101, Dover 19904, Kent, Delaware, United States of America. Each of WHG (International) Limited and WHG Trading Limited is registered in Gibraltar and has its registered office at 6/1 Waterport Place, Gibraltar. Unless specifically indicated otherwise, the contents of this e-mail are subject to contract; and are not an official statement, and do not necessarily represent the views, of William Hill PLC, its subsidiaries or affiliated companies. Please note that neither William Hill PLC, nor its subsidiaries and affiliated companies can accept any responsibility for any viruses contained within this e-mail and it is your responsibility to scan any emails and their attachments. William Hill PLC, its subsidiaries and affiliated companies may monitor e-mail traffic data and also the content of e-mails for effective operation of the e-mail system, or for security, purpose! s. ********************************************* _______________________________________________ cisco-nsp mailing list [email protected] https://puck.nether.net/mailman/listinfo/cisco-nsp archive at http://puck.nether.net/pipermail/cisco-nsp/
