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New Member

Adding extra outbound port

i have an ASA-5510 and there are 4 physical Rj45 ports but when i open ASDM i can only see and configure 3 ports. i already have INTERNAL, EXTERNAL and DMZ configured but i am planning to add 1 more channel for an External network. how can i do this? and is this even possible at all?

what i want is to have my web server and exchange in the DMZ with a dedicated external line and another external line for a faster internet subscription but this will not have a static public IP.

INTERNAL network will access WEB Server and Exchange via the DMZ but all internet access will be through EXTERNAL2 (dynamic IP). all web queries to our web server and exchange shall go through EXTERNAL1 (static IP).

thanks for help in advance.

New Member

Re: Adding extra outbound port

Do a 'sh ver' to check your licensing - you may only have a license for 3 physical interfaces. If that's the case, you could create subinterfaces on one port to get around this limitation.

New Member

Re: Adding extra outbound port

honestly i do not know how to make that subport. can you please guide me through it. and i also do not work through the shell. i use ASDM. thanks in advance!

New Member

Re: Adding extra outbound port

I don't typically use the ASDM, but I do know that you would go to Configuration -> Device Setup ->Interfaces -> Add interface.

Also, whatever device this trunk would go to would need to be enabled for 802.1q trunking as well.

Here are some basic instructions for using the CLI:

To add a subinterface and assign a VLAN to it, perform the following steps:


Step 1 To specify the new subinterface, enter the following command:

hostname(config)# interface physical_interface.subinterface

The subinterface ID is an integer between 1 and 4294967293.

For example, enter the following command:

hostname(config)# interface gigabitethernet0/1.100

Step 2 To specify the VLAN for the subinterface, enter the following command:

hostname(config-subif)# vlan vlan_id

The vlan_id is an integer between 1 and 4094. Some VLAN IDs might be reserved on connected switches, so check the switch documentation for more information.

You can only assign a single VLAN to a subinterface, and not to the physical interface. Each subinterface must have a VLAN ID before it can pass traffic. To change a VLAN ID, you do not need to remove the old VLAN ID with the no option; you can enter the vlan command with a different VLAN ID, and the security appliance changes the old ID.

Step 3 To enable the subinterface, enter the following command:

hostname(config-subif)# no shutdown

To disable the interface, enter the shutdown command.

If you use subinterfaces, you typically do not also want the physical interface to pass traffic, because the physical interface passes untagged packets. Because the physical interface must be enabled for the subinterface to pass traffic, ensure that the physical interface does not pass traffic by leaving out the nameif command. If you want to let the physical interface pass untagged packets, you can configure the nameif command as usual.