Brocade Network OS Administrator’s Guide v4.1.1 - Manual (Page 674)

Principal routing bridge availability
If a new principal routing bridge is introduced into a working VCS Fabric cluster, or if the principal
routing bridge is lost and a new switch must be elected, the fabric is rebuilt from the control-plane
viewpoint, whereas the data plane continues to forward traffic without disruption. The primary
responsibilities of the principal routing bridge in a VCS Fabric are:
• RBridge ID allocation
• Ownership of virtual management IP address
• Keeping the configuration database synchronized
Brocade trunks
Brocade trunks is the only aggregation method that works using ISLs.
Brocade ISL trunks are formed automatically with other switches using Line Reset (LR) primitives
signaling with the peer switch.
All ISL ports connected to the same neighbor Brocade switch attempt to form a trunk. For a successful
trunk formation, all ports on the local switch must be part of the same port group and must be
configured at the same speed. The number of ports allowed per trunk group is six. The trunk is turned
on by default.
The table below shows the allocation of port numbers to port groups for Brocade VDX switches.
Port groups TABLE 99
Brocade platform Port groups No. of port groups per
platform
VDX 6710 te0/1–te0/6 4
gi0/1–gi0/14
gi0/15–gi0/27
gi0/28–gi0/48
VDX 6720-24 (10Gbe) 1–12, 13–24 2
VDX 6720-60 (10Gbe) 1–10, 11–20, 21–30, 31–40, 41–50, 51–60 6
VDX 6730-32 (10Gbe) 1–12, 13–24 2
VDX 6730-76 (10Gbe) 1–10, 11–20, 21–30, 31–40, 41–50, 51–60 6
VDX 6740 (10Gbe) 1–16, 17–32, 33–40, 41–48 4
VDX 8770 (with VDX LC48x1G line
card) 1–8, 9–16, 17–24, 25–32, 33–40, 41–48 6 per 1G blade
VDX 8770 (with VDX LC48x10G line
card) 1–8, 9–16, 17–24, 25–32, 33–40, 41–48 6 per 10G blade
VDX 8770 (with VDX LC12x40G line
card) 1–2, 3–4, 5–6, 7–8, 9–10, 11–12 6 per 40G blade
NOTE
Brocade trunks are not supported over 1-Gbps links.
To utilize the advantages of Brocade trunking between VDX switches, Brocade recommends having at
least a two-member trunk and multiple ECMP paths. Brocade also recommends routing the cables in a
trunk through separate conduits to ensure connectivity in case a conduit is accidentally cut.
Principal routing bridge availability
674 Network OS Administrator’s Guide
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