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New Member

unable to ping subinterface

Hi there,

Wondeirng if someone can help me.\

im trying to configure a new vlan to be used for wifi guest access.

i have configured the vlans on my access points and switches.

i have an ASA firewall and i have created a new sub interface in vlan 999.  see config below:

interface Ethernet0/2

description Connected to Inside

nameif inside

security-level 100

ip address


interface Ethernet0/2.2

vlan 999

nameif vlan999

security-level 90

ip address


i have logged into the switch and i am unable to ping the new subinterface.  obviously works fine if i ping it from the asa.

am i missing something out?

Everyone's tags (3)

unable to ping subinterface

  Sure the fw is not blocking ping from the outside ? 

New Member

unable to ping subinterface

hey there! thanks for the reply!

hmm the firewall is blocking ping from the outside

the subinterface i created is on the inside interface, and im trying to ping it from an internal switch.

Re:unable to ping subinterface

If the ping is hitting the inside interface first, that's your problem. You can only ping the ingress interface on an ASA, not across interfaces like a router. If you create a layer 3 SVI on the switch for vlan 999 and ping the firewall, that should be successful.


Sent from Cisco Technical Support Android App

New Member

unable to ping subinterface

hi there, thanks for the reply.

ahh ok, how do i create a layer 3 svi on the switch?should i found this link:

What i am trying to do is provide guest wifi.  Does this setup sound ok?


inside interface /24 - for LAN

inside subinterface /24 in VLAN999- Isolated LAN for WiFi


VLAN999 created and ports added to this VLAN

i was trying to ping from this device but it was failing


Access Points have been configured for WiFi

Second WiFi configured and in vlan999

Access points plugged into ports on switch that are in vlan1 and vlan999

thanks again

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