MC/SG: Lan Card Backup: is the MAC address of the main card transferred to the standby card?

[Enrico Venturi]

Hi everybody,
if I configure lan1 card as backup of lan0 card when
lan0 fails the IP address of lan0 is assigned to lan1, ok.
But what's about the MAC address? Is it transferred
to lan1?

It seems the answer is "NOT", but I heard by someone that this could be true (optional packages? .. ?)
If OTS9000 manages 802.3 subnets what does it happen when the lan1 is switched ON?
If the MAC address changes then the OTS9000 / 802.3 subnet reconfiguration is needed, then the reboot (!!!) of the node is requested, and this cannot be accepted ---> to switch the package on the standby node is better!
If the MAC address can be transferred to lan1 then ... what's about OTS9000??
Thank you for the reply.

Have a nice day.

[boley janowski · Accepted solution]

vi /etc/rc.config.d/hpconf

=ioscan -funC lan

here is an example of my /etc/rc.config.d/hpeisabtconf file.


HP_EISABT_INTERFACE_NAME[0]=lan1
HP_EISABT_STATION_ADDRESS[0]=#
HP_EISABT_SPEED[0]=100HD


on the "HP_EISABT_STATION_ADDRESS[0]=" put the MAC address of you lan0 card for your lan1 card. when the lan1 is activated it will assign the card the MAC you specify in this file if you leave it blank it will take it default.

good luck

[boley janowski]

please remember to assign points or N/A this helps us and your stats so you can continue to get the help when you ask for it.

[melvyn burnard]

Having MAC addresses changed in a package in ServiceGuard is not supported, and can caus eproblems.

[Carlos Uribe]

had anyone already probed this configuration in the netconf with the mac address on service guard? does it work? has any problem?

Thanks

[Carsten Krege]

Quoted from the SG manual, "Managing MC/ServiceGuard", Dec 2000, available on
http://docs.hp.com/hpux/pdf/B3936-90045.pdf

p.79
"In the case of a local network switch, TCP/IP connections are not lost for Ethernet, but IEEE
802.3 connections will be lost. Ethernet, Token Ring and FDDI use the ARP protocol, and HP-UX sends out an unsolicited ARP to notify remote systems of address mapping between MAC (link level) addresses and IP level addresses."

This means that arp is used to notify remote devices about the new(!) mapping of IP and MAC address. The MAC address is not switched!

Even more clear:

p. 275:

Previous generation HA software would move the MAC address of the network card along with the IP address when services were moved to a
backup system. This is no longer allowed in MC/ServiceGuard.


Do not download MAC addresses to LAN interfaces in a SG environment. This can cause severe problems.

Carsten