Brocade Fabric Manager Administrator's Guide v6.1.0 (53-10000610-02, June 2008)

298 Fabric Manager Administrator’s Guide
53-10000610-02
FCIP tunnel management
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How MTU Suggest works
When you click Suggest, Fabric Manager performs an IPPerf test on both ends of the tunnel.
This utility determines the maximum transmission unit (MTU) that can be sent and received.
NOTE
When you use the shortcut option to launch the IP Perf or Verify IP Connectivity dialog box from
the GigE Port tab, all monitored fabrics care displayed. Expand the fabric tree node to display
FCIP-capable switches only.
It works by sending the largest possible size packet across the tunnel being tested. It waits for
a reply, and continues sending at different packet sizes until it determines the largest size
packet that returns a valid connection response. In this way, IPPerf determines the largest
usable MTU. MTU settings must match at both ends of the tunnel.
FCIP tunnel management
After an FCIP tunnel has been configured with Fabric Manager, you can perform the following
administration tasks on that tunnel:
• “Viewing FCIP tunnel Information” on page 298
• “Modifying FCIP tunnels” on page 299
• “Disabling FCIP tunnels” on page 300
• “Re-enabling disabled FCIP tunnels” on page 300
• “Deleting FCIP tunnels” on page 300
You can view information about one FCIP tunnel at a time whether that tunnel is active or only
configured.
If an IP network is changed or a configuration mismatch occurs, you may need to modify an existing
FCIP tunnel. Modifying an FCIP tunnel deletes the existing one and creates a new one.
There are many reasons for disabling or re-enabling existing tunnels. This can be to stop traffic
while you are diagnosing an IP problem, or replacing a cable. The process is similar for both
actions.
Deleting an FCIP tunnel removes all of the configuration information. You cannot undelete a tunnel,
you must recreate it.
Viewing FCIP tunnel Information
1. Select the appropriate tab for the information you want to view:
To view information about any configured FCIP tunnel, select the FCIP Tunnel tab in the
Detailed Information panel.
To view information about an active FCIP tunnel, select the FCIP Tunnel Link tab in the Detailed
Information panel.
The details dialog displays with the basic details visible on the Basic tab and the advanced
details visible on the Advanced tab, as shown in Figure 197.