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need your thoughts on this, i have a switch that runs on 1000mb Full duplex and a firewall with 100Mb Full duplex, is there a possibility traffic wont pass through?

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up vote 0 down vote accepted

If both interfaces are configured to autonegotiate their speed/duplex settings, then you won't have a problem.

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so if my switch is fixed to 1000Mb and my Firewall to 100Mb auto-nego, still wouldn't work? – user1666411 Oct 22 '13 at 3:39
You can't force a 100mb NIC to operate at 1000mb just because the other end is forced to 1000mb. – fukawi2 Oct 22 '13 at 3:41
Why is your switch fixed to 1000? That's actually somewhat against protocol, as per spec, GigE requires autoneg. – EEAA Oct 22 '13 at 3:41
my initial thought was, it will just slow down the traffic even though the other is fixed 1000Mb and the other is 100Mb. i was just curious to know.. – user1666411 Oct 22 '13 at 3:43
The traffic transiting the firewall will never exceed 100Mbps no matter what the switch port is configured to, so configuring the switch port to 100Mbps isn't going to "slow" anything down. – joeqwerty Oct 22 '13 at 3:55

What you ought to do is to configure the switch port that the firewall connects to so that it matches the firewall interface. Hard code the speed/duplex settings on both sides of the connection to 100Mbps/Full Duplex.

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