Reference Guide

new link prior to the rest of the fabric. For devices on those two switches, when they attempt to start using the new link, Two-hop
Lossless DLS ensures that the routes are ready for use prior to their route updates.
For a switch that is directly connected to one of the two switches with the new link, when it performs the rebalance operation, its device
traffic is shifted to the new path in a lossless manner. If the new path to which traffic is being shifted to is up to two hops (one of which
includes the new link), Two-hop Lossless DLS ensures that the routes along that two-hop path are ready for use.
NOTE
If a fabric shortest path that includes the new link is longer than two hops, when the switches perform their rebalancing
operations, the traffic may still experience I/O disruptions and/or out-of-order frame delivery.
Once the new hop has been established, all later route updates use the standard lossless DLS capabilities.
∙ Two-hop Lossless DLS has the same platform and ISL technology restrictions as the Lossless DLS feature.
∙ Two-hop Lossless DLS is not supported with TI zones due to non-deterministic ordering of events when multiple ISLs come
online at the same time.
∙ Two-hop Lossless DLS is not supported with any hops to or through an FC router related domain (front and translate domains).
∙ Two-hop Lossless DLS is not supported over logical ISLs (LISLs).
∙ You must manually enable this feature on all switches to get the desired results.
Configuring Two-hop Lossless DLS
The dlsSet and dlsShow commands have been updated to support the new twohop option. The dlsReset command resets the state of
DLS in port-based routing. The state of lossless, two-hop and eportbal are set using the dlsSet command. The dlsSet command now
accepts a new twohop option to enable or disable the two-hop lossless DLS feature.
sw_79:root> dlsset --help
dlsset usage:
dlsset
dlsset --enable -lossless
dlsset --disable -lossless
dlsset --enable -twohop
dlsset --disable -twohop
dlsset --enable -eportbal
dlsset --disable -eportbal
dlsset --rebalance
dlsset --rebalance -all
The dlsShow command displays the state of the
Two-hop Lossless DLS enhancement when it has been enabled. If the enhancement is
disabled, the original default output is displayed.
sw_79:root> dlsshow
DLS is set with Two-hop Lossless enabled
E_Port Balance Priority is not set
Frame Redirection
Frame Redirection provides a means to redirect traffic flow between a host and a target that use virtualization and encryption
applications, such as the Brocade SAS blade and Brocade Data Migration Manager (DMM), so that those applications can perform
without having to reconfigure the host and target. You can use this feature if the hosts and targets are not directly attached.
Frame Redirection depends on the wide distribution of the Defined Zone Database. The Defined Zone Database on Fabric OS switches
is pushed out to all other Fabric OS switches in the fabric that support Frame Redirection. Redirection zones exist only in the defined
configuration and cannot be added to the effective configuration.
Routing Traffic
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