topic Re: issue in connecting to WLC 2100 via switch in Wireless

issue in connecting to WLC 2100 via switch

ciscoroyzhang — Sun, 04 Jul 2021 06:06:39 GMT

Hi there, I am trying to setup my lap with a new WLC 2100. but failed to connect to the WLC via second switch.

In WLC 2100, fa0/2 connect to the second switch, Fa0/1 connect to PC.

In second switch 3560, it's fa0/2 connect to the WLC as trunk port. port fa0/1 is in vlan 1

Management int ip in WLC is 192.168.1.1 in VLAN 1 assoicarted with port is fa0/1, the PC ip is 192.168.1.2.

When PC connect via fa0/1 in WLC, I can ping 192.168.1.1 from PC. but connect PC to fa0/1 in 3560, no reply.

To my understanding, fa0/2 in WLC is trunk port by default and the vlan1 is allowed, since fa0/2 in 3560 also configured trunk, there is no reason, why I can not ping the WLC. any suggestion ?

Re: issue in connecting to WLC 2100 via switch

Scott Fella — Mon, 26 Nov 2012 03:50:50 GMT

Well the main thing is if your tagging the management interface or not. If you tag it with '0' then native vlan on the trunk port would be 1. If you set the tag as '1' then the WLC is actually tagging vlan 1 and might be the cause of your issue.

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Re: issue in connecting to WLC 2100 via switch

George Stefanick — Mon, 26 Nov 2012 03:53:14 GMT

What Scott said ... See attached its set to 254 which means its TAGGING 254.. If its blank.. Then nothing is being tagged ..

BTW -- Happy Thanksgiving Scott !

__________________________________________________________________________________________
"Satisfaction does not come from knowing the solution, it comes from knowing why." - Rosalind Franklin
__________________________________________________________________________________________
‎"I'm in a serious relationship with my Wi-Fi. You could say we have a connection."

Re: issue in connecting to WLC 2100 via switch

Scott Fella — Mon, 26 Nov 2012 03:56:54 GMT

Happy belated Thanksgiving to you to George.

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issue in connecting to WLC 2100 via switch

ciscoroyzhang — Mon, 26 Nov 2012 05:25:38 GMT

Hi guys, I have tried to change the management Vlan to 0 in WLC and same issue persists? what is next step to check which issue could be? Thanks...

Re: issue in connecting to WLC 2100 via switch

George Stefanick — Mon, 26 Nov 2012 05:57:10 GMT

Roy

Lets get back to basics. Take the port going to the wlc and make it vlan 1 and not trunk. On the wlc make sure the vlan ID is blank not zero.

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Re: issue in connecting to WLC 2100 via switch

Saravanan Lakshmanan — Mon, 26 Nov 2012 18:59:00 GMT

George, vlan id is an mandatory config on wlc to create an interface, it can't be blank is what i believe.

Roy,

WLC vlan 0 == untagged, anything other than 0 is tagged on WLC side. Port that is mapped with vlan id 0 only on WLC is an access port, it'll become trunk once an tagged vlan is mapped to that port with or without vlan id 0.

if you've vlan id set 0 on WLC then it communicates to an native/untagged vlan on switch side.

(Cisco didn't change this airespace style vlan stuff yet)

WLC Switch

vlanID 0 Native/Untagged vlan X

vlanID 5 Tagged vlan 5

does show arp switch on wlc and switch shows the arp learnings on each side, if not there could be vlan id issue between wlc and switch.

Re: issue in connecting to WLC 2100 via switch

George Stefanick — Mon, 26 Nov 2012 19:06:11 GMT

I stand corrected .. You are correct 0 is untagged .. Thanks for the correction .. +5

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issue in connecting to WLC 2100 via switch

Saravanan Lakshmanan — Mon, 26 Nov 2012 19:43:26 GMT

Thank you!!!

Re: issue in connecting to WLC 2100 via switch

ciscoroyzhang — Mon, 26 Nov 2012 22:27:28 GMT

Hi Saravanan/George, thanks for this clearification.

WLC = Switch this make it much easy to understander the WLC.

OK, Further to Saravanan's comment, can I make following conclution:

all ports in WLC by default are trunk port.

port in WLC - if assicated with vlanID 0 - that port is access port and allow that native vlan only

Port in WLC - if assicated with valn ID other than 0. - port is trunk port, it will allow both that vlan and other vlan (include natvie vlan.)

based on above, the WLC port connecting to the second switch should be in default state (trunk port), and the port in second switch connect to this port should be configured as trunk port accordingly.

If mananagment Vlan is in VLAN ID0 and associated with WLC fa0/1, that fa0/1 should only used for connect to a PC for web access to the WLC.

if above statement is correct, I will try again in my lab as following:

On WLC (2100)

Interface VLAN IP add assoicated local port

managment interface Vlan id 0 192.168.1.1 fa0/1

AP management int Vlan id 0 192.168.1.2 fa0/2

trunk to the Swich trunk(default) n/a fa0/3

On Second Switch (3560)

Interface VLAN IP add assoicated local port

trunk to the WLC trunk (dot1q) n/a fa0/3

Acces port to PC valn1 default 192.168.1.8 fa0/1

with this configuration in WLC and Swich, I should be able to ping the managment interface, AP managment interface from PC.

in addition to above, If I add dynamic interface in WLC for SSID with vlan 10, providing I have router connect to the 3560 switch with subinterafce setup, I should be able to ping valn 10 ip add from my PC as well? please let me know if you have any commnet, I will give a try in my lab and update you later.... once again thanks both for help....

Re: issue in connecting to WLC 2100 via switch

ciscoroyzhang — Mon, 26 Nov 2012 23:11:42 GMT

Hi Guys,

I have just configure the WLC as above and the result is nagtive.

plug PC to Switch fa0/1 no reply

plug PC directly to the WLC fa0/1 no reply. (was replying first time when I configure the WLC)

seem to me there might be some error in the intial configuration in WLC, since the initial configure is very simple, I post it as following, please help to see if there is any error:

after reset to factory default in WLC 2100:

Would you like to terminate autoinstall? [yes]: yes

System Name [Cisco_32:18:a0] (31 characters max):
AUTO-INSTALL: process terminated -- no configuration loaded

Enter Administrative User Name (24 characters max): admin
Enter Administrative Password (3 to 24 characters): ********
Re-enter Administrative Password : ********

Management Interface IP Address: 192.168.1.1
Management Interface Netmask: 255.255.255.0
Management Interface Default Router: 192.168.1.25
Management Interface VLAN Identifier (0 = untagged): 0
Management Interface Port Num [1 to 8]: 1
Management Interface DHCP Server IP Address: 192.168.1.25

AP Manager Interface IP Address: 192.168.1.2

AP-Manager is on Management subnet, using same values
AP Manager Interface DHCP Server (192.168.1.25):

Virtual Gateway IP Address: 1.1.1.1

Mobility/RF Group Name: MRF-GP

Network Name (SSID): TEST

Configure DHCP Bridging Mode [yes][NO]: yes
Warning! Enabling Bridging mode will disable Internal DHCP server and DHCP Proxy feature.
May require DHCP helper functionality on external switches.

Allow Static IP Addresses [YES][no]: yes

Configure a RADIUS Server now? [YES][no]: no
Warning! The default WLAN security policy requires a RADIUS server.
Please see documentation for more details.

Enter Country Code list (enter 'help' for a list of countries) [US]: au

Enable 802.11b Network [YES][no]: yes
Enable 802.11a Network [YES][no]: yes
Enable 802.11g Network [YES][no]: yes
Enable Auto-RF [YES][no]: yes

Configure a NTP server now? [YES][no]: no
Configure the system time now? [YES][no]: no

Warning! No AP will come up unless the time is set.
Please see documentation for more details.

Configuration correct? If yes, system will save it and reset. [yes][NO]:yes

... ... ... ... ... ... ... ... ... ...

show interface summary

Interface Name                   Port Vlan Id       IP Address           Type        Ap Mgr    Guest
-------------------------------- ---- -------- --------------- ------- ------ -----
ap-manager                       1    untagged      192.168.1.2            Static       Yes        No
management                       1   untagged      192.168.1.1           Static       No          No
virtual                                        N/A N/A           1.1.1.1                 Static       No           No

Re: issue in connecting to WLC 2100 via switch

Carlos Leiton — Tue, 27 Nov 2012 00:24:31 GMT

Hello Roy

Starting from the last configuration that you added:

show interface summary

Could you please let me know how is the switch-port configured for the WLC and the switchport going to the PC?

Also, what is the PC IP address?

Please notice that you can't configure the PC IP address of 192.168.1.2 as that IP is the one of the ap-manager interface.

Also, from the WLC CLI, please issue a:

- show port summary

I'll be waiting these outputs.

Re: issue in connecting to WLC 2100 via switch

ciscoroyzhang — Tue, 27 Nov 2012 01:05:02 GMT

Hi Carlos thanks for the reply, please be adviced that I can ping the WLC management interface if I plug into WLC port fa0/1 now.

other comments please see bellow:

Could you please let me know how is the switch-port configured for the WLC and the switchport going to the PC?

Switch port to the WLC configure as trunk port
Switch port ot the PC no configure, by default it is in vlan 1.
we know native vlan in Switch 3560 is VLAN 1, is that correct the vlan with id 0 is natvie vlan in 2100? if that is the case, it should be able to travel via the trun port.

Also, what is the PC IP address?

192.168.1.8

Also, from the WLC CLI, please issue a: - show port summary

STP Admin Physical Physical Link Link

Pr Type Stat Mode Mode Status Status Trap POE

-- ------- ---- ------- ---------- ---------- ------ ------- ---------

1 Normal Disa Enable Auto Auto Down Enable N/A

2 Normal Disa Enable Auto Auto Down Enable N/A

3 Normal Forw Enable Auto 100 Full Up Enable N/A

4 Normal Disa Enable Auto Auto Down Enable N/A

5 Normal Disa Enable Auto Auto Down Enable N/A

6 Normal Disa Enable Auto Auto Down Enable N/A

7 Normal Disa Enable Auto Auto Down Enable Enable (Power Off)

8 Normal Disa Enable Auto Auto Down Enable Enable (Power Off)

issue in connecting to WLC 2100 via switch

Saravanan Lakshmanan — Tue, 27 Nov 2012 01:06:39 GMT

On WLC, can't add same vlan to two different physical port. Having that said if the untagged vlan "0" is already mapped to a port then it'll be unavailable on other port(s), same applicable to tagged vlans. However, it is not applicable for AP-Manager interface.

all ports in WLC by default are trunk port -> NO, see my previous post.

port in WLC - if assicated with vlanID 0 - that port is access port and allow that native vlan only -> Yes, it is untagged(there is no native vlan concept on WLC)

Port in WLC - if assicated with valn ID other than 0. - port is trunk port, it will allow both that vlan and other vlan (include natvie vlan.) -> No, it allows only the mapped vlan(s) on the port, if the mapped vlan doesn't have the untagged vlan then it won't forward it.

If mananagment Vlan is in VLAN ID0 and associated with WLC fa0/1, that fa0/1 should only used for connect to a PC for web access to the WLC -> Yes, it is untagged so PC can talk.

with this configuration in WLC and Swich, I should be able to ping the managment interface, AP managment interface from PC -> show the respective switch side config.

Re: issue in connecting to WLC 2100 via switch

Carlos Leiton — Tue, 27 Nov 2012 01:10:38 GMT

Ok this is your problem:

The WLC 2106, 2112 or 2125 can only have one physical port connected to a switch.

On this case, if you take a look the management and ap-manager interface are currently mapped to port 1.

However "port 1" is disabled and you have port 3 connected and enabled, but you do not have any WLC interface mapped to port 3.

According to your current configuration, and according to the best practices, all the traffic of the WLC will go through port 1.

issue in connecting to WLC 2100 via switch

Saravanan Lakshmanan — Tue, 27 Nov 2012 01:16:54 GMT

I guess you're thinking that physical port that is not configured will be trunk and will forward all the traffic, that is incorrect. you've to map interfaces to all the physical port that you're planning to use. WLC != switch.

Re: issue in connecting to WLC 2100 via switch

nikhilcherian — Tue, 27 Nov 2012 02:54:43 GMT

my 2 cents..

if you are connecting multiple WLC ports to the switch ports, make sure you have 1 AP manager configured per WLC port, else you will see packet drops..

Re: issue in connecting to WLC 2100 via switch

ciscoroyzhang — Tue, 27 Nov 2012 03:10:11 GMT

Hi Saravanan, tried your suggestion: all the vlan assoicated with the trunk port in WLC, everything works fine.

Thanks for the help....

Also many thanks to Geoge, Carlos and Scott for your patience and support...

issue in connecting to WLC 2100 via switch

Saravanan Lakshmanan — Tue, 27 Nov 2012 06:28:03 GMT

WLC doesn't allow mapping more than one ap manager per port.

AP-Manager responds only to udp 5246 and 5247 not even icmp when dynamic interface configured as ap manager.

Having said that, Are you saying having multiple ap manager(s) using same vlan and subnet interface mapped to different physical port will have issues when they connect to a switch. i'd not think since WLC doesn't do wired LAN to LAN bridging like switch, so no question for looping so there is no need for stp on wlc. think of wlc as multi homed PC. you could try to create looping between w.less and wired lan by connecting the wgb to wlc wirelessly while its wired port of wgb looped to the WLC's interface or using winxp PC bridged btw wired and wireless interface.

issue in connecting to WLC 2100 via switch

nikhilcherian — Tue, 27 Nov 2012 08:34:30 GMT

-----------------------

I agree with your point here,that is what i mentioned in my comment -"

if you are connecting multiple WLC ports to the switch ports, make sure you have 1 AP manager configured per WLC port, else you will see packet drops.."-

-----------------

multiple ap-managers should be there ( one per wlc physical port), if he is connecting the multiple WLC ports to the switch