| Author |
Can you change the Mac address
|
|
| Randhir 2002-06-17, 9:44 am |
| Can you change the Mac address of a particular interface on a Cisco Router.. | |
| ciscoteacher 2002-06-17, 11:20 am |
| Not without changing the hardware module (assuming it is a modular router). | |
| jeff_j_black 2002-06-17, 11:51 am |
| The MAC address is supposed to be hard coded into ROM. I have seen some NICs that would let you program a Administered Address, but I have not heard of this for Cisco cards. | |
| Zimovets 2002-06-18, 4:38 am |
| Dear jeff_j_black
How can You explain following snapshot?:
ekb-r2#
ekb-r2#config term
Enter configuration commands, one per line. End with CNTL/Z.
ekb-r2(config)#int e0
ekb-r2(config-if)#mac-address ?
H.H.H MAC address
ekb-r2(config-if)#mac-address
IMHO You're a bit wrong. 
You can change MAC address of ethernet interface at least.
With best regards. | |
| Imran4sin 2002-06-18, 4:47 am |
| Sup,
I have to agree with jeff_j_black on this one.
As far as i know a MAC( Media Access Control) is burned on the Etheret Card(NIC) by the manufacturer on the ROM(readOnlyMemo).
So there is no way yoiu can change it, its unique to every other network device. Compared with IP , which you can easily change.
I dunno about the snap shot that youve got...but yea.. i dont think MAC can be edited with out changing the whole device it self.
aiigth,
l8r, | |
| Zimovets 2002-06-18, 5:25 am |
| Hello, Imran4sin!
Have You tried it yourself?
I have. And with C2509/IOS 12.0.21a
MAC address was changed.
I know it's BIA address, though in my young late 80s it was possible to change MAC address of NICs(at least 3Com). Why shoud it be changed now?
With best regards | |
|
| the ability to change mac addy differs with version/hardware.
do a show interface ether for example and you will see a hardware address and a burn in address.
you can manually change it or an upper layer protocol can change it such as DECnet. (too much CIT )
with hsrp, you will also see virtual mac address come into play.
Router# show interfaces ethernet 0
Ethernet 0 is up, line protocol is up
Hardware is MCI Ethernet, address is aa00.0400.0134 (via 0000.0c00.4369)
taken from sample display at (yes, I am too lazy to fire up the router so you have to settle for cisco!  plus you get to see it yourself. too lazy to find link that directly address this issue but this should show that its possible at the very least.
http://www.cisco.com/univercd/cc/td...tm#xtocid244138
other sample
Router# show interfaces tokenring
TokenRing 0 is up, line protocol is up
Hardware is 16/4 Token Ring, address is 5500.2000.dc27 (bia 0000.3000.072b)
edit: I should note, you don't actually change the bia, its in rom.
additional edit: I been up all nite for the japan and now the korea game and it is currently 4:40 am so I will not be responsible for any error! | |
| Imran4sin 2002-06-18, 5:41 am |
| ****************
Hello, Imran4sin!
Have You tried it yourself?
I have. And with C2509/IOS 12.0.21a
MAC address was changed.
***************
Sup,
dude..u serious.. dammn i need to up date mi self...
cheers for that..will look at it..
aiiiigth,
l8r, | |
| jeff_j_black 2002-06-18, 9:40 am |
| So the conlusion is: yes depending on platform and IOS version? | |
| Randhir 2002-06-19, 1:29 am |
| Rightly said Jeff_Black..... It all depends on Router version you are Using | |
| Randhir 2002-06-19, 3:07 am |
| At the end I ahve one more ques Can you change the mac addy of a part. int of switch..
I think someone said yes we can change the mac addy of a interface of a switch..I have never checked that one but check it out.....
mac-adderss-table restricted static 00a0... e0/4
mac-address-table restricted static 001a... e0/2 e0/5
show mac-address-table | |
| jeff_j_black 2002-06-19, 9:46 am |
| Thanks Randhir, very helpful! |
|
|
|