Troubleshooting Web Authentication
After you configure web authentication, if the feature does not work as expected, complete these
troubleshooting steps:
Check if the client gets an IP address. If not, users can uncheck
DHCP Required
on the WLAN and
give the wireless client a static IP address. This assumes association with the access point. Refer to
the
IP addressing issues
section of
Troubleshooting Client Issues in the Cisco Unified Wireless
Network for troubleshooting DHCP related issues
.
1.
On WLC versions earlier than 3.2.150.10, you must manually enter
https://1.1.1.1/login.html
in
order to navigate to the web authentication window.
The next step in the process is DNS resolution of the URL in the web browser. When a WLAN client
connects to a WLAN configured for web authentication, the client obtains an IP address from the
DHCP server. The user opens a web browser and enters a website address. The client then performs
the DNS resolution to obtain the IP address of the website. Now, when the client tries to reach the
website, the WLC intercepts the HTTP Get session of the client and redirects the user to the web
authentication login page.
2.
Therefore, ensure that the client is able to perform DNS resolution for the redirection to work. On
Windows, choose
Start > Run
, enter
CMD
in order to open a command window, and do a nslookup
www.cisco.com" and see if the IP address comes back.
On Macs/Linux: open a terminal window and do a nslookup www.cisco.com" and see if the IP
address comes back.
If you believe the client is not getting DNS resolution, you can either:
Enter either the IP address of the URL (for example, http://www.cisco.com is
http://198.133.219.25)
♦
Try to directly reach the controller's webauth page with
https:///login.html. Typically this is http://1.1.1.1/login.html.
♦
Does entering this URL bring up the web page? If yes, it is most likely a DNS problem. It might also
be a certificate problem. The controller, by default, uses a self−signed certificate and most web
browsers warn against using them.
3.
For web authentication using customized web page, ensure that the HTML code for the customized
web page is appropriate.
You can download a sample Web Authentication script from Cisco Software Downloads. For
example, for the 4400 controllers, choose
Products > Wireless > Wireless LAN Controller >
Standalone Controllers > Cisco 4400 Series Wireless LAN Controllers > Cisco 4404 Wireless
LAN Controller > Software on Chassis > Wireless Lan Controller Web Authentication
Bundle−1.0.1
and download the
webauth_bundle.zip
file.
These parameters are added to the URL when the user's Internet browser is redirected to the
customized login page:
4.
ap_mac The MAC address of the access point to which the wireless user is associated.
♦
switch_url The URL of the controller to which the user credentials should be posted.
♦
redirect The URL to which the user is redirected after authentication is successful.
♦
statusCode The status code returned from the controller's web authentication server.
♦
wlan The WLAN SSID to which the wireless user is associated.
♦
These are the available status codes:
Status Code 1: "You are already logged in. No further action is required on your part."
♦
Status Code 2: "You are not configured to authenticate against web portal. No further action
is required on your part."
♦
Status Code 3: "The username specified cannot be used at this time. Perhaps the username is
already logged into the system?"
♦
Status Code 4: "You have been excluded."
♦
Status Code 5: "The User Name and Password combination you have entered is invalid.
Please try again."
♦
All the files and pictures that need to appear on the Customized web page should be bundled into a
.tar file before uploading to the WLC. Ensure that one of the files included in the tar bundle is
login.html. You receive this error message if you do not include the login.html file:
Refer to the Guidelines for Customized Web Authentication section of Wireless LAN Controller Web
Authentication Configuration Example for more information on how to create a customized web
authentication window.
Note:
Files that are large and files that have long names will result in an extraction error. It is
recommended that pictures are in .jpg format.
5.
Internet Explorer 6.0 SP1 or later is the browser recommended for the use of web authentication.
Other browsers may or may not work.
6.
Ensure that the
Scripting
option is not blocked on the client browser as the customized web page on
the WLC is basically an HTML script. On IE 6.0, this is disabled by default for security purposes.
7.
Note:
The Pop Up blocker needs to be disabled on the browser if you have configured any Pop Up
messages for the user.
Note:
If you browse to an
https
site, redirection does not work. Refer to Cisco bug ID CSCar04580
(registered customers only) for more information.
If you have a
host name
configured for the
virtual interface
of the WLC, make sure that the DNS
resolution is available for the host name of the virtual interface.
Note:
Navigate to the
Controller > Interfaces
menu from the WLC GUI in order to assign a
DNS
hostname
to the virtual interface.
8.
Sometimes the firewall installed on the client computer blocks the web authentication login page.
Disable the firewall before you try to access the login page. The firewall can be enabled again once
the web authentication is completed.
9.
Topology/solution firewall can be placed between the client and web−auth server, which depends on
the network. As for each network design/solution implemented, the end user should make sure these
ports are allowed on the network firewall.
Protocol
Port
HTTP/HTTPS Traffic
TCP port 80/443
CAPWAP Data/Control Traffic
UDP port 5247/5246
LWAPP Data/Control Traffic
(before rel 5.0)
UDP port 12222/12223
EOIP packets
IP protocol 97
Mobility
UDP port 16666 (non
secured) UDP port 16667
(secured IPSEC tunnel)
10.
For web authentication to occur, the client should first associate to the appropriate WLAN on the
WLC. Navigate to the
Monitor > Clients
menu on the WLC GUI in order to see if the client is
associated to the WLC. Check if the client has a valid IP address.
11.
Disable the Proxy Settings on the client browser until web authentication is completed.
12.
The default web authentication method is PAP. Ensure that PAP authentication is allowed on the
RADIUS server for this to work. In order to check the status of client authentication, check the
debugs and log messages from the RADIUS server. You can use the
debug aaa all
command on the
WLC to view the debugs from the RADIUS server.
13.
Update the hardware driver on the computer to the latest code from manufacturer's website.
14.
Verify settings in the supplicant (program on laptop).
15.
When you use the Windows Zero Config supplicant built into Windows:
Verify user has latest patches installed.
♦
Run debugs on supplicant.
♦
16.
On the client, turn on the EAPOL (WPA+WPA2) and RASTLS logs from a command window, Start
> Run > CMD:
netsh ras set tracing eapol enable
netsh ras set tracing rastls enable
In order to disable the logs, run the same command but replace enable with disable. For XP, all logs
will be located in C:\Windows\tracing.
17.
If you still have no login web page, collect and analyze this output from a single client:
debug client
debug dhcp message enable
18.
debug aaa all enable
debug dot1x aaa enable
debug mobility handoff enable
If the issue is not resolved after you complete these steps, collect these debugs and use the TAC
Service Request Tool (registered customers only) in order to open a Service Request.
debug pm ssh−appgw enable
debug pm ssh−tcp enable
debug pm rules enable
debug emweb server enable
debug pm ssh−engine enable packet
