Brocade FastIron Ethernet Switch Platform and Layer 2 Switching Configuration Guide - Manual (Page 87)

secondary interfaces on the Master node. Configuring multiple rings enables you to use all the ports in
the ring. The same port can forward traffic one ring while blocking traffic for another ring.
Syntax: [no] enable
The enable command enables the ring.
Changing the hello and preforwarding times
You also can change the RHP hello time and preforwarding time. To do so, enter commands such as
the following.
device(config-vlan-2-mrp-1)#hello-time 200
device(config-vlan-2-mrp-1)#preforwarding-time 400
These commands change the hello time to 200 ms and change the preforwarding time to 400 ms.
Syntax: [no] hello-time ms
Syntax: [no] preforwarding-time ms
The ms specifies the number of milliseconds. For the hello time, you can specify from 100 - 1000 (one
second). The default hello time is 100 ms. The preforwarding time can be from 200 - 5000 ms, but must
be at least twice the value of the hello time and must be a multiple of the hello time. The default
preforwarding time is 300 ms. A change to the hello time or preforwarding time takes effect as soon as
you enter the command.
Configuration notes for changing the hello and preforwarding times
• The preforwarding time must be at least twice the value of the hello time and must be a multiple of
the hello time.
• If UDLD is also enabled on the device, Brocade recommends that you set the MRP preforwarding
time slightly higher than the default of 300 ms; for example, to 400 or 500 ms.
• You can use MRP ring diagnostics to determine whether you need to change the hello time and
preforwarding time. Refer to Metro Ring Protocol diagnostics on page 87.
Metro Ring Protocol diagnostics
The Metro Ring Protocol (MRP) diagnostics feature calculates how long it takes for RHP packets to
travel through the ring. When you enable MRP diagnostics, the software tracks RHP packets according
to their sequence numbers and calculates how long it takes an RHP packet to travel one time through
the entire ring. When you display the diagnostics, the CLI shows the average round-trip time for the
RHP packets sent since you enabled diagnostics. The calculated results have a granularity of 1
microsecond.
Enabling MRP diagnostics
To enable MRP diagnostics for a ring, enter the following command on the Master node, at the
configuration level for the ring.
device(config-vlan-2-mrp-1)#diagnostics
Syntax: [no] diagnostics
Changing the hello and preforwarding times
FastIron Ethernet Switch Platform and Layer 2 Switching Configuration Guide 87
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