Re: [Devil-linux-develop] /etc/udev/rules.d/70-persistent-net.rules and /etc/mactab

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OK, thanks everyone.

Taking on board everyone's comments to date, I'll combine my initial bug/feature requests into a new proposal.

As the absence of "70-persistent-net.rules" may not generate the NIC assignments in the same order (which I agree could be disastrous for a firewall) then I now think that the present behaviour of save-config including "70-persistent-net.rules" should be retained.

My test-environment on a usb-stick (used on differing hardware) is conceptually the same as Stefan's requirement to fail-over a saved config onto a cold standby box. While the impact on my usb test-build to correct persistent mac assignment is no real problem, if you are failing over a firewall you want a speedy swapover with as little messing as possible, assuming always that you have configured this upfront.

Just patching /etc/init.d/network to call /sbin/nameif to align interfaces and mac-addresses will not, on it's own, address this scenario.

What enabling a call to nameif and mactab does do is allow an administrator to take control of interface assignment, rather than having to work with whatever udev saves in 70-persistent-net.rules.

My colleague Roy (the "linux-nut" of previous posts) has a proof-of-concept bash-script that reads a separate new config file /etc/mactable.conf pre-populated with multiple interface/mac-address details from *both* the current-active and the cold-standby hardware, and greps to populate /etc/mactab with only the entries relating to addresses discovered by "ifconfig -a". This would need to be called earlier in the startup sequence than network startup, which would then find a valid /etc/mactab for the booting hardware.

Sequencing would need to be as follow (pseudo code):

        if /etc/mactable.conf exists
                then create or overwrite /etc/mactab from /etc/mactable.conf
        fi
        if /etc/mactab exists
                then call nameif to use it
        else
                use the current behaviour (Eg: 70-persistent-net.rules)
        fi

So, if the requirement is to assign mac addresses to specific devices on a single system edit /etc/mactab, or If the requirement is to assign differect mac addresses to specific devices on a failover systems edit /etc/mactable.conf.

Does this sound to be a way forward?

Regards - Steve.