I have aPIX 515 firewall.  I try to configure subinterfaces on a physical interface which is connected to a trunk port on a layer 2 switch.

Please help.

Thank you
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There is no other way than to use VLANs.
The PIX interface will be configured as trunk, while for each VLAN you will configure subinterfaces. Assign one VLAN ID per interface


interface GigabitEthernet0/1

description "Trunk Connectivity with SW"

speed 100

duplex full

no nameif

no security-level

no ip address

interface GigabitEthernet0/1.100

vlan 100

nameif VLAN100

security-level 80

ip address xxxxxxx


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SavvisAuthor Commented:
Hi pschakravarthi,
I tried this:
LABFW(config)# int e1
LABFW(config)#no ip address

LABFW(config)# int e1.2
LABFW(config)#nameif ethernet1.2 vlan2 security90
LABFW(config)#ip address vlan2

LABFW(config)# int e1.3
LABFW(config)#nameif ethernet1.3 vlan3 security80
LABFW(config)#ip address vlan3

But it idn't work.
Please what else should to do.


did you configure you're uplink port also as trunk?
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SavvisAuthor Commented:
Hi zwart072,

What do you mean by "uplink port" ?
My layer switch with 2 vlans works OK when connected to simple trunk link to a router.
But I failed to use it on the PIX:
A pc on vlan2 with this ip:, gateway (E1.2 of the PIX) cannot ping
the gateway.  I don't know why?
the port where you are connecting your pix on the switch must be configured as trunk (encapsulation dot1q) port.
SavvisAuthor Commented:
Hi All,

The issue is version

I upgraded the PIX from 6.3(4) to 7.2(2).  

Everything works OK now.

SavvisAuthor Commented:
SavvisAuthor Commented:
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