03-28-2013 10:59 AM - edited 07-03-2021 11:48 PM
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 ?
03-28-2013 11:00 AM
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
03-28-2013 11:13 AM
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
03-28-2013 11:18 AM
What would be that theoretical max on concurrent users ? Thank you for posting the other thread it confirms my suspicions.
03-28-2013 11:23 AM
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
04-01-2013 10:29 AM
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.
04-01-2013 11:33 AM
Hi,
why would you connect the AP to a trunk port?
are you using FlexConnect? with local switching?
Find answers to your questions by entering keywords or phrases in the Search bar above. New here? Use these resources to familiarize yourself with the community: