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NIC MAC address change

NIC MAC address change

In trying to move an application from Alpha to Itanium, I find I have to make the Itanium have the same MAC address as the Alpha as I cannot change the Siemens S5 PLC comms.

How can I change the MAC address on the Itanium?

I know I can't have 2 machines with the same MAC address, so I will be disconnecting one or the other as needed for tests...
5 REPLIES
Hoff
Honored Contributor

Re: NIC MAC address change

There's the hardware or physical Media Access Control (MAC) address, and that's somewhat more tough to change. There's the physical MAC address, and that can be changed from host-level software; DECnet sets the physical MAC, for instance. That's a $qio call.

As for changing the MAC address, the hardware or physical address can be a PROM. It's somewhat more difficult to change, particularly without the identity of the NIC. Some boxes can have it soft-loaded, some have a socketed PROM, and some can't be changed short of drastic measures.

Which NICs? That'll identify the soft-loaded or socketed stuff.

The best approach here is probably finding a MAC NAT box; basically, a box or switch that remaps the MAC addresses on the fly. That'll get you out of the current mess. There are fancy names for this MAC NAT; HP calls it "virtual connect" or some such, IIRC.

Re: NIC MAC address change

OK.

It looks like the NICs are BCM5704.

The output from a 'show dev /full' and 'tcpip show int/full' is in the attached file.

Also included is info from
LANCP> sh conf
LANCP> sh dev/char

Thanks,
D

Re: NIC MAC address change

My attach didn't!

Here's the info...

Here's what a show device tells me:

$ sh dev ewa0/full

Device EWA0:, device type BCM5704, is online, network device, error logging is
enabled, device is a template only.

Error count 2 Operations completed 0
Owner process "" Owner UIC [SYSTEM]
Owner process ID 00000000 Dev Prot S:RWPL,O:RWPL,G,W
Reference count 0 Default buffer size 512
Current preferred CPU Id 0 Fastpath 1
Current Interrupt CPU Id 0

Operating characteristics: Link up, Full duplex, Autonegotiation.

Speed (Mbits/sec) 100
Def. MAC addr 00-1C-C4-FB-DC-B3 Current MAC addr 00-1C-C4-FB-DC-B3
$ sh dev ewb0/full

Device EWB0:, device type BCM5704, is online, network device, error logging is
enabled, device is a template only.

Error count 2 Operations completed 0
Owner process "" Owner UIC [SYSTEM]
Owner process ID 00000000 Dev Prot S:RWPL,O:RWPL,G,W
Reference count 0 Default buffer size 512
Current preferred CPU Id 1 Fastpath 1
Current Interrupt CPU Id 1

Operating characteristics: Link up, Full duplex, Autonegotiation.

Speed (Mbits/sec) 100
Def. MAC addr 00-1C-C4-FB-DC-B2 Current MAC addr 00-1C-C4-FB-DC-B2

$ tcpip sh int/full
Interface: LO0
IP_Addr: 127.0.0.1 NETWRK: 255.0.0.0 BRDCST:
MTU: 4096
Flags: UP LOOP NOARP MCAST SMPX
RECEIVE SEND
Packets 0 0
Errors 0 0
Collisions: 0

Interface: WE0
IP_Addr: 200.200.200.25 NETWRK: 255.255.255.0 BRDCST: 200.200.200.255
Ethernet_Addr: 00-1C-C4-FB-DC-B3 MTU: 1500
Flags: UP BRDCST RUN MCAST SMPX
RECEIVE SEND
Packets 1681 30
Errors 0 0
Collisions: 0

Interface: WE1
IP_Addr: 120.102.41.213 NETWRK: 255.255.255.0 BRDCST: 120.102.41.255
Ethernet_Addr: 00-1C-C4-FB-DC-B2 MTU: 1500
Flags: UP BRDCST RUN MCAST SMPX
RECEIVE SEND
Packets 12692991 11065
Errors 0 0
Collisions: 0

LANCP> sh conf

CSNCGL LAN Configuration (15-DEC-2009 09:59:33.09):
Parent or
Device PrefCPU Medium/User Version Link Speed Duplex Auto BufSize MAC Address Type Description
------ ------- ----------- ------- ---- ----- ------ ---- ------- ---------------- ------------ -----------
EWA0 0 Ethernet X-78 Up 100 Full Yes 1500 00-1C-C4-FB-DC-B3 UTP Merl5704
EWB0 1 Ethernet X-78 Up 100 Full Yes 1500 00-1C-C4-FB-DC-B2 UTP Merl5704
LANCP> sh dev/char

CSNCGL Device Characteristics EWA0 (15-DEC-2009 10:00:13.00):
Value Characteristic
----- --------------
1500 Device buffer size
Normal Controller mode
External Internal loopback mode
00-1C-C4-FB-DC-B3 Default MAC address (Hardware LAN address)
Multicast address list
Ethernet Communication medium
FF-FF-FF-FF-FF-FF MAC address (Current LAN address)
128 Minimum receive buffers
256 Maximum receive buffers
Yes Full duplex enable
Yes Full duplex operational
00-1C-C4-FB-DC-B3 MAC address (Current LAN address)
TwistedPair Line media type
100 Line speed (mbps)
Enabled Auto-negotiation
Enabled Flow control
Disabled Jumbo frames
0 Failover priority
Link Up Link state

CSNCGL Device Characteristics EWB0 (15-DEC-2009 10:00:13.00):
Value Characteristic
----- --------------
1500 Device buffer size
Normal Controller mode
External Internal loopback mode
00-1C-C4-FB-DC-B2 Default MAC address (Hardware LAN address)
Multicast address list
Ethernet Communication medium
FF-FF-FF-FF-FF-FF MAC address (Current LAN address)
128 Minimum receive buffers
256 Maximum receive buffers
Yes Full duplex enable
Yes Full duplex operational
00-1C-C4-FB-DC-B2 MAC address (Current LAN address)
TwistedPair Line media type
100 Line speed (mbps)
Enabled Auto-negotiation
Enabled Flow control
Disabled Jumbo frames
0 Failover priority
Link Up Link state
Hoff
Honored Contributor

Re: NIC MAC address change

Go look at the Broadcom Corporation NetXtreme BCM5704 NIC to see if the chips are socketed; while I'd tend to guess not, but it can be worth a look.

Changing the address can be done via sys$qio. See the network driver information in this manual:

ftp://ftp.hp.com/pub/openvms/doc/AA-PV6SG-TK.PDF

Or Google for examples of using the NMA$C_PCLI_PHA itemcode.

Re: NIC MAC address change

Can this be done at system level? LANCP? or OTHER?