Show dhcp vlan on router

[michaelpatoc811211471]

Hi Guys,

I'm new in cisco. I'm not familiar on how to show the dhcp vlan on cisco router. The router is configured as router on a stick, 2 dhcp pool created for internet access only. We have other vlans that didn't connect to the internet and no dhcp pool created.

Cisco router is also connected into firewall,  setup of static route in the firewall.

-destination ip -> vlan
-Interface -> LAN
-Gateway -> cisco router.

Thank you in advance.

Regards,

Mike

[Georg Pauwen]

Hello,

not sure what you are looking for. Do you want to see the current DHCP leases ? Or is the problem that you don't have Internet from your router (and from whatever is attached to it) ?

[michaelpatoc811211471]

Hi Georg,

I'm looking the output of available ip addresses per vlan in the cisco router.

example.

   -> vlan 10 and vlan 20 is used for internet access.

   -> vlan 30,40 and 50 - no internet access but I want to check the available ip addresses for the said vlans.

I can check the dhcp leases for the vlan 10 and 20 however no output for the rest vlans since they don't connected to the internet.

Hope you understand my explanation.

Regards,

Mike

[Georg Pauwen · Accepted solution]

Hello,

I don't think there is a direct command to achieve that. A possible 'workaround' would be to configure Netflow and Top Talkers"

Configure your SVIs like this:

interface vlan 30
ip flow ingress
ip flow egress
!
interface vlan 40
ip flow ingress
ip flow egress
!
interface vlan 50
ip flow ingress
ip flow egress

Then, configure 'ip flow-top-talkers' on your router:

ip flow-top-talkers
top 200
sort-by bytes

You can check which IP addresses are in use by using the command below. The drawback is that you are limited to the number 200, so if you have more than 200 users in one Vlan, they won't all show up.

show ip flow top

[michaelpatoc811211471]

Hi Georg,

Thank you for your assistance and swift response.

Regards,

Mike