topic Wireless Questions / Concerns in Wireless

Wireless Questions / Concerns

NC16390371 — Sun, 04 Jul 2021 06:48:36 GMT

I have some questions with regards to WLAN designs.

The 1st question is - I would like to use a /21 subnet for a campus and would like to know if there are any issues with regards to using this size of subnet for that many clients.

The 2nd question is - I would like to better understand the "spanning-tree portfast trunk" command on a port that has an access point connection. I would like to configure the port as follows:

interface gi6/xx

switchport access vlan 100

switchport mode trunk

switchport native vlan 100

switchport trunk vlan allowed 100,200,300,400

spanning-tree portfast trunk

As I understand it under rapid-spanning tree portfast on access ports is "globally" enabled however on a trunk it is disabled. The fact that it is disabled would indicate that every client that connects to that access point is subjected to the spanning-tree check hence waiting upwards of 30 sec before it can be allowed on the network. Am I correct in my assumptions ?

Wireless Questions / Concerns

NC16390371 — Thu, 28 Mar 2013 18:00:57 GMT

Correction :

interface gi6/xx

switchport access vlan 100

switchport mode trunk

switchport trunk native vlan 100

switchport trunk vlan allowed 100,200,300,400

spanning-tree portfast trunk

Wireless Questions / Concerns

Stephen Rodriguez — Thu, 28 Mar 2013 18:13:33 GMT

The /21 shouldn't be a problem, so long as you do not exceed the maximum number of concurrent users the WLC can handle.

as for the portfast trunk, take a look here:

https://supportforums.cisco.com/thread/2075017

HTH,
Steve

------------------------------------------------------------------------------------------------
Please remember to rate useful posts, and mark questions as answered

Wireless Questions / Concerns

NC16390371 — Thu, 28 Mar 2013 18:18:08 GMT

What would be that theoretical max on concurrent users ? Thank you for posting the other thread it confirms my suspicions.

Wireless Questions / Concerns

Stephen Rodriguez — Thu, 28 Mar 2013 18:23:11 GMT

Depends on the platform.

5008 - 7000 clients

WiSM2 - 15000

for two examples. The data sheet for your particular model will have this informationl.

HTH,
Steve

------------------------------------------------------------------------------------------------
Please remember to rate useful posts, and mark questions as answered

Wireless Questions / Concerns

Abhishek Abhishek — Mon, 01 Apr 2013 17:29:24 GMT

Hello ,

As per your 1st question - I would like to use a /21 subnet for a campus and would like to know if there are any issues with regards to using this size of subnet for that many clients.

I can suggest you that there will be no problem to use /21 subnet for a campus but you should keep in mind not to exceed maximum number of WLC can support.

Now as per your 2nd question - I would like to better understand the "spanning-tree port fast trunk" command on a port that has an access point connection. I would like to configure the port as follows:

I can see as per your configurations you are using port-fast on access ports globally. As Port Fast immediately transitions the port into STP forwarding mode upon linkup. You won’t have to wait for 30 seconds for the client to be allowed in the network.

Wireless Questions / Concerns

Yahya Jaber — Mon, 01 Apr 2013 18:33:37 GMT

Hi,

why would you connect the AP to a trunk port?

are you using FlexConnect? with local switching?