Enabling Loop Monitoring; Configuring The Switch For Interoperability - Cisco DS-C9216I-K9 Configuration Manual

Enabling Loop Monitoring

Enabling Loop Monitoring
When a disk is removed from a loop port, the loop stays active based on the bypass circuit. Thus the disk
removal is not known until you try to communicate with the disk. To detect such removals, the disks can
be polled periodically (every 20 seconds) using the fcinterop loop-monitor command. This command
enables loop polling for FL ports in a Cisco MDS 9000 Family switch. By default, the fcinterop
loop-monitor command is disabled.
Caution Changes to the loop monitoring feature should be made by an administrator or individual who is
completely familiar with switch operations.

Configuring the Switch for Interoperability

Interoperability enables multiple vendor products come into contact with each other. Fibre Channel
standards guide vendors towards common external Fibre Channel interfaces.
If all vendors followed the standards in the same manner, then interconnecting different products would
become a trivial exercise. However, not all vendors follow the standards in the same way thus resulting
in interoperability modes. This section briefly explains the basic concepts of these modes.
Each vendor has a regular mode and an equivalent interoperability mode, which specifically turns off
advanced or proprietary features and provide the product with a more amiable standards compliant
implementation.
Table 31-2
are specific to switches in the Cisco MDS 9000 Family while in interop mode.
Table 31-2
Switch Feature
Domain IDs
Timers
F_S_TOV
D_S_TOV
E_D_TOV
Cisco MDS 9000 Fabric Manager Switch Configuration Guide
31-6
lists the changes in switch behavior when you enable interoperability mode. These changes
Changes in Switch Behavior When Interoperability Is Enabled
Changes if Interoperability is Enabled
Some vendors cannot use the full range of 239 domains within a
fabric.
Domain IDs are restricted to the range 97-127. This is to
accommodate the McData nominal restriction to this same
range. They can either be setup statically (the MDS will only
accept one domain ID, if it does not get that domain ID it isolates
itself from the fabric), or preferred. (If it does not get its
requested domain ID, it accepts any assigned domain ID.)
All Fibre Channel timers must be the same on all switches as
these values are exchanged by E ports when establishing an ISL.
The timers are:
Verify that the Fabric Stability Time Out Value timers match
exactly.
Verify that the Distributed Services Time Out Value timers
match exactly.
Verify that the Error Detect Time Out Value timers match
exactly.
Chapter 31 Advanced Features and Concepts
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