How can I add the 3rd ethernet card ?

["Stellar R'espree" <stellar@softforum.co.kr>]

Hi,

I use a PC linux machine with 2 ethernet cards. (one for eth0, the other
for eth1).
And now, I want to add third ethernet card.

It is recognized as eht2 at my machine, but when I tried to following
command,

    /sbin/ifconfig eth2 123.123.123.123 broadcast 123.123.123.255
netmask 255.255.255.0

it prints following error message.

    SIOCSIFFLAGS: Try again

Do you know what the problem is ?

Thanks in advance.

stellar

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