Brocade Multi-Service IronWare Multiprotocol Label Switch (MPLS) Configuration Guide (Supporting R05.6.00) - Manual (Page 539)

Multi-Service IronWare Multiprotocol Label Switch (MPLS) Configuration Guide 515
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VPLS MAC age timer configuration overview
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There is an existing CLI to configure a global timer that controls MAC aging in the system (software
cache). However, this configuration is not being applied to the age timers used for MAC entries
associated with VPLS instances. Consequently, the age timer for VPLS MAC entries becomes
hard-coded.
The VPLS application has separate age timers for different types of entries, local and remote. Prior
to NetIron R05.5.00, the timer for the remote entries is calculated as two times the age timer of
local entries, in which the remote age timer is coupled with the local one, which may be
undesirable.
It is highly desirable to make age timers fully adjustable through CLI so that you can tune the
system to function most effectively based on the deployment and specific configurations.
Issues with timers
Prior to NetIron R05.5.00, there were the following issues with the timers:
• Software MAC age timers for VPLS are NOT adjustable
In releases prior to NetIron R05.5.00, CLI mac-age-time that configures a global timer which
controls MAC aging in the software cache for regular L2 is not being applied for MAC entries
associated with VPLS instances. The age timers for VPLS MAC entries become hard-coded.
• The age timer for VPLS remote entries is coupled with the local entries’ in values
VPLS applications actually have separate age timers for different types of entries, local and
remote. Prior to NetIron R05.5.00, the timer for the remote entries is calculated as two x the
age timer of local entries, which may not be desirable.
Solution
The benefit of configurable MAC age timers is that you can tune your systems to function most
effectively based on the deployment and on a specific configuration.
With NetIron R05.5.00:
• The VPLS age timers are fully configurable for both local and remote entries.
• The formula “2 x” between the local timer and the remote timer is removed. Now, you have the
flexibility to specify values for the age timers from 60 - 65535 seconds independently for the
local and the remote entries.
• The values are bound by the same global system range shared with the regular MAC entries.
The default values remains the same, which is 300 seconds for VPLS local entries and 600
seconds for the remote entries.
• Age time “0” disables the software aging. VPLS MAC follows the same format to be consistent.
However, the value “0” is hidden as the valid range.
• show mpls vpls summary displays the age timers on MP.
• show mpls vpls displays the age timers on LP.
• show running config displays the age timers when their value becomes none, the default.
• show mac vpls displays value “0” for age field that is associated with a MAC entry when you
disable the software aging prior to stop the traffic.
• When the software aging is disabled after the hardware aging is activated and the software
aging has already started, the age field displays the time value that had been elapsed prior to
the aging being disabled.