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I have an ASA 5505 and a Cisco switch. I am trying to hook them up together.

The ASA has an IP of

Servers on the VLAN 1102 on the switch has a default gateway of

I do a show vlan command on the switch, the port gi1/16 shows up on the switch under vlan 1102.

When I plug the ASA into gi1/16, it disappears from "show vlan" on the switch on 1102.

I plug a server directly into the VLAN 1102 and set a default gateway of and it gets internet fine.

I try the same with a server on another switch (that is connected to that switch) under vlan 1102 and it does not work! What am i doing wrong?

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I tried, but I'm having trouble understanding what's where and why. You mentioned that the port 'disappears' from show vlan, have you check the actual interface/port status once it's connected? You might need to do some work on your question – l0c0b0x Feb 18 '11 at 0:14
I do't quite understand you question (it needs to be woreded clearer), but I think you are having a problem with DTP? Sound like you are plugging a server into a switch port and it drops into vlan 1106 but when you plug the ASA into the same switch port, it is no longer an vlan 1106 access port? This is because it may be negotiating into a trunk port? – jwbensley Aug 13 '12 at 12:37

Make sure your ASA and server ports on the switch are "access" ports in VLAN 1102. After you correctly configured the switch you can verify the 1102 VLAN with "sh mac address-table Vlan 1102" command. There must be two MAC's in the list.

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