Brocade Network OS Administrator’s Guide v4.1.1 - Manual (Page 125)

Upgrading nodes by using an odd/even approach
To reduce downtimes during planned software upgrades, the network design illustrated here has been
provisioned with redundancy in all layers. Once such in-built redundancy is in place, an "odd/even"
approach is used, whereby the cluster is split equally into odd and even nodes that represent both sides
of the redundant traffic path. Therefore, both groups (either all odd or all even) have traffic connectivity
to all hosts and end devices during the upgrade process. As a result, reloading any one group results in
minimal traffic loss.
The following summarizes the classification of the odd and even nodes that were tested.
Classification of odd and even nodes TABLE 14
Position Chassis type Description Odd group Even group
Leaf VDX 6720-60 Dual-homed TOR
VDX sw81 sw79
Spine VDX 6720-24 Dual-homed sw87 sw86
Servers ESX 5.1 with
Brocade CNA Dual-homed to both
leaf nodes through a
vLAG
Preparing for the maintenance window
Do the following before the start of the maintenance window.
1. Take a "golden" snapshot of the running configuration, by copying the running configuration onto
flash or an external FTP or SCP server. The following copies the running configuration to flash
memory.
sw87# copy running-config flash://running.Config.master
2. Establish Telnet connections and console connections to all VDX Fabric cluster nodes. Telnet
sessions are used to perform configurations, while console sessions are used to monitor the
switches.
3. View the running configuration (as illustrated below) to ensure that all the port-channel interfaces
have been configured by means of the vlag ignore-spit command on all VDX nodes.
NOTE
By default, port-channel configurations have "vlag ignore-split" enabled. However, if this default has
been changed it must be re-established.
sw87# conf t
Entering configuration mode terminal
sw87(config)# int po 6144
sw87(config-Port-channel-6144)# vlag ignore-split
sw87(config-Port-channel-6144)# exit
sw87(config)# exit
sw87#
sw87# show running-config interface Port-channel 6144
interface Port-channel 6144
vlag ignore-split
switchport
switchport mode trunk
switchport trunk allowed vlan all
switchport trunk tag native-vlan
no shutdown
Upgrading nodes by using an odd/even approach
Network OS Administrator’s Guide 125
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