Figure 77 Ex_Port Phantom Switch Topology - HP SN3000B Administrator's Manual

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Fibre Channel routing concepts
Front domain 1
(FC router 1)
FIGURE 77
All EX_Ports or VEX_Ports connected to an edge fabric use the same xlate domain ID for an
imported edge fabric; this value persists across switch reboots and fabric reconfigurations.
If you lose connectivity to the edge fabric because of link failures or the IFL being disabled, xlate
domains remain visible. This prevents unnecessary fabric disruptions caused by xlate domains
repeatedly going offline and online due to corresponding IFL failures. To remove the xlate domain
from the backbone, refer to
The combination of front domains and xlate domains allows routing around path failures, including
path failures through the routers. The multiple paths to an xlate domain provide additional
bandwidth and redundancy.
There are some differences in how the xlate domain is presented in the backbone fabric. The
backbone xlate domains are topologically connected to FC routers and participate in FC-FC routing
protocol in the backbone fabric. Front domains are not needed in the backbone fabric. As in the
case of an xlate domain in an edge fabric, backbone fabric xlate domains provide additional
bandwidth and redundancy by being able to present themselves as connected to single or multiple
FC routers with each FC router capable of connecting multiple IFLs to edge fabrics.
Use the fcrXlateConfig command to display or assign a preferred domain ID to a translate domain
or, in some scenarios, to prevent the creation of an unnecessary xlate domain. Refer to the Fabric
OS Command Reference for more details about this command.
Identifying and deleting stale xlate domains
If a remote edge fabric goes unreachable, the xlate domains created in other edge fabrics for this
remote edge fabric are retained and not removed unless there is any disruption in the local edge
fabric.
You can use the fcrXlateConfig command to identify and remove these stale xlate domains without
disrupting the fabric.
474
Host 1
Fabric 1
Xlate domain 1
(Fabric 2)
Target 1' Target 2'
EX_Port phantom switch topology
"Identifying and deleting stale xlate domains."
Front domain 2
(FC router 2)
Xlate domain 2
(Fabric 3)
Target 3'
Fabric OS Administrator's Guide
53-1002446-01