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Troubleshooting your switch or WCCP router deployment

Troubleshooting tips for both switch and router deployments  Top

The following table shows several items to check if you encounter problems while testing transparency settings in the Appliance Manager. Select the troubleshooting actions based on the protocols for which you are setting up transparent proxying.

Action

Applicable protocols

Details

Check that the devices in your transparency deployment are accessible.

DNS
FTP
HTTP
NNTP
MMS
RTSP

At a client computer, complete the following steps from the command line:

  1. Ping the IP address of the router.
  2. Ping the IP address of the appliance.

Confirm that the request is being sent through the switch or WCCP router.

DNS
FTP
HTTP
NNTP
MMS
RTSP

Trace the route of a client request to the target server to ensure that the requests are being sent through the switch or WCCP router. A tool such as traceroute for UNIX can help you trace the route of requests.

Check whether the client is connected to the streaming media cache.

MMS
RTSP

Complete the following steps:

  1. At a client computer that is excluded from transparent proxying, request the media stream that the user reported was not working.
  2. Check the Streaming access log to determine if the client connected to the streaming media cache.

If the stream is not delivered or if it is not playing as you expect, a problem with the MMS or RTSP transparent proxying configuration on the appliance might exist.

Check whether the client is connected to the streaming server.

MMS
RTSP

In the Appliance Manager, select Data tab > Streaming > Detailed Statistics. View the detailed statistics to determine whether the client is connected to the streaming server.

Transparent proxying of MMS or RTSP service is working if you see an entry with the IP address of the client from which you made the media request and the name of the media file that you requested. Transparent proxying of MMS or RTSP is not working if no entry exists.

Check whether the streaming media configuration options are configured correctly.

MMS
RTSP

In the Appliance Manager, select Setup tab > Streaming Media > RTSP and MMS. Verify the following on the pages:

  • MMS, RTSP, or both (as applicable) are enabled.
  • All relevant streaming media options are configured.

    All options relevant to the streaming protocol that you are deploying are required.

See the online Help for information about configuring these settings.

Check whether the transparency settings are configured correctly.

DNS
FTP
HTTP
NNTP
MMS
RTSP

Check the Transparency and IP Spoofing Enable page to see if transparent proxying is enabled for all the protocols you are deploying transparently.

For WCCP router deployments only

If you configure the WCCP options in the Transparency pages for a particular protocol but forget to enable transparency for that protocol, the IP address of the appliance appears in the router configuration in the list of Web caches, news caches, and streaming media caches that the router is aware of. However, the appliance does not service any requests.

Check the Transparency - WCCP Service groups page to see if WCCP is enabled for the protocols you are deploying transparently.

Compare the WCCP service group information you set on the appliance to the service group information configured on the WCCP router to see if:

  • The service group numbers match the service groups configured on the WCCP router.
  • If you configured a WCCP password, it matches the password you configured on the router for the same service group.

Also check whether you set the port settings correctly, as described in Determining port numbers for redirected traffic.

Check the WCCP statistics on the appliance.

DNS
FTP
HTTP
NNTP
MMS
RTSP

The WCCP statistics on the WCCP - General page in the Appliance Manager are useful for debugging problems with your transparent proxy deployment with a WCCP router. These statistics show totals for all service groups to which this appliance belongs. However, by enabling and disabling some settings on the Transparency and IP Spoofing Enable page, you can determine whether WCCP is working for specific service groups.

You can view statistics for only one service group by doing the following:

  1. Select Setup tab > Transparency > Transparency and IP Spoofing Enable. Disable WCCP for all but one protocol. Commit your changes.
  2. Select Data tab > WCCP > General. Record the numbers shown in the WCCP statistics.
  3. Send a request of the type of protocol for which WCCP is enabled.
  4. Check the WCCP statistics on the WCCP - General page again to determine if the numbers increased. If they have, you know that WCCP is working for the service group (protocol) for which WCCP is enabled.

    Note
    It is not necessary to start with the statistics showing 0. For this test, you are trying to determine if the WCCP router and the appliance are communicating, rather than looking at the actual numbers.

  5. Repeat Steps 1 through 4 for each of the protocols for which you are configuring transparent proxying with a WCCP router.

Check whether the switch is configured correctly.

DNS
FTP
HTTP
NNTP
MMS
RTSP

Check the switch to confirm that the switch is configured to pass to the appliance requests of the protocols for which you are deploying transparent proxying.

If the switch is configured incorrectly, your appliance might not receive any traffic. If your switch is configured correctly and you can confirm that the appliance is receiving traffic, verify that your routing scheme is configured so that NetCache can send requests to the WAN.

For MMS and RTSP, ensure that the switch is configured to pass requests for both TCP and UDP to the streaming media cache. If your deployment includes RTSP for QuickTime, ensure that you have specified the RTCP port and that you have configured the switch to pass traffic for the RTCP port to the appliance.

For FTP, ensure that the switch is set to redirect port 21 requests to this appliance and no other.

Note
Do not set proto any on Alteon switches.

Check whether the router is configured correctly.

DNS
FTP
HTTP
NNTP
MMS
RTSP

On the router, use WCCP commands described in your WCCP documentation to troubleshoot your WCCP router configuration. Check the following:

  • Ensure that the router is configured to pass requests for all protocols for which you are deploying transparent proxying to the appliance.
  • Ensure that the service group for each protocol in your transparent proxy deployment is enabled on the router.
  • For each service group, ensure that you have entered the following command to apply a filter to the router's outbound (or inbound for IP spoofing) interface. Otherwise, the router cannot redirect the appropriate packets to a appliance.

    For HTTP (Standard Service Group 0), enter the following at the command line:

    ip wccp web-cache   redirect out
    

    For NNTP, MMS, or RTSP, enter the following at the command line:

    ip wccp n   redirect out 
    

    In the preceding example, out represents the router's outbound interface. If you want to redirect inbound traffic, specify the following:

    ip wccp n   redirect in
    
  • Determine whether the router is aware of all appliances that belong to the same service group as the router.

    For HTTP, enter the following at the command line:

    show ip wccp web-cache detail
    

    For NNTP, MMS, or RTSP, enter the following at the command line:

    show ip wccp n detail
    

    where n is the number of the service group for which you want to list members.

Check whether the router is configured correctly (continued).

DNS
FTP
HTTP
NNTP
MMS
RTSP

  • Determine if the optional WCCP password that you configured on the router for the service group matches the WCCP password that you configured on the Create a WCCP Service page for the same service group.
  • Turn on the wccp debug mode, as necessary, to obtain more debug information on the router.
  • For MMS and RTSP, ensure that the router is configured to pass requests for both TCP and UDP to the streaming media cache.
  • For FTP, ensure that the router is set to redirect port 21 requests to this appliance and no other.

Check the WCCP statistics on the router.

DNS
FTP
HTTP
NNTP
MMS
RTSP

Check the statistics on the router.

  1. For HTTP, enter the following command:

    show ip wccp web-cache

  2. For FTP, NNTP, MMS, and RTSP, enter the following command:
    show ip wccp n
    

    where n is the service group number of the protocol for which you are testing.

  3. Record the Number of Cache Engines and Total Packets Redirected values.
  4. Submit a request.
  5. Check the router statistics again, comparing the number shown in the Total Packets Redirected statistic to the number you recorded previously for this statistic.

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