Chassis Discovery Policy
The chassis discovery policy determines how the system reacts when you add a new Cisco UCS S3260 chassis or an existing standalone Cisco UCS S3260 chassis to a Cisco UCS system. Cisco UCS S3260 System Architectural Overview describes the connectivity for a Cisco UCS S3260 system managed by Cisco UCS Manager. Cisco UCS Manager uses the settings in the chassis discovery policy to determine whether to group links from the system I/O controllers (SIOCs) to the fabric interconnects in fabric port channels.
To add a previously standalone Cisco UCS S3260 chassis to a Cisco UCS system, you must first configure it to factory default. You can then connect both SIOCs on the chassis to both fabric interconnects. After you connect the SIOCs on the chassis to the fabric interconnects, and mark the ports as server ports, chassis discovery begins.
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Chassis/IOM acknowledgement after chassis/FEX discovery policy changes is not applicable for S3260 chassis. |
Server Discovery
Cisco UCS Manager automatically discovers the Cisco UCS S3260 server nodes after the Cisco UCS S3260 chassis is discovered.
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Server discovery fails if the SIOC corresponding to the server is not present. |
Link Grouping
In release 4.0(1a), Link Group Preference is automatically set to Port Channel when using new SIOC with PCIe slots.
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For the Cisco UCS 6400 Series Fabric Interconnect, and Cisco UCS 6536 Fabric Interconnect, the Link Group Preference is always set to Port Channel. |
When you connect a Cisco UCS S3260 chassis through a FEX to directly to a Cisco UCS 6300 Series fabric interconnect, or Cisco UCS 6400 Series Fabric Interconnect, and Cisco UCS 6536 Fabric Interconnect, Cisco UCS Manager ignores the Port Channel preference and the SIOCs operate in the non-port channel mode.
Set the link grouping preference to None if the Cisco UCS S3260 chassis is connected to a fabric interconnect through a single 10G cable.
After changing the Link Group Preference value in the Cisco UCS Manager GUI, Decommission and then Recommission the Cisco UCS S3260 chassis for the change to take effect.
In the Cisco UCS domain, if there are other chassis operating in Port Channel mode, do the following:
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Discover the chassis in the Cisco UCS system with the Link Group Preference set to Port Channel
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Change the link aggregation preference for the Cisco UCS S3260 chassis through Chassis Connectivity Policy
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Decommission the chassis
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Recommission the chassis
Configuring the Chassis/FEX Discovery Policy
Procedure
Command or Action | Purpose | |||
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Step 1 |
UCS-A# scope org / |
Enters the root organization mode.
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Step 2 |
UCS-A /org # scope chassis-disc-policy |
Enters organization chassis/FEX discovery policy mode. |
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Step 3 |
(Optional) UCS-A /org/chassis-disc-policy # set descr description |
(Optional)
Provides a description for the chassis/FEX discovery policy.
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Step 4 |
UCS-A /org/chassis-disc-policy # set link-aggregation-pref {none | port-channel} |
Specifies whether the links from the SIOCs or FEXes to the fabric interconnects are grouped into a port channel. Link aggregation can be one of the following:
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Step 5 |
UCS-A /org/chassis-disc-policy # commit-buffer |
Commits the transaction to the system configuration. |
Example
The following example scopes to the default chassis discovery policy, provides a description for the policy, sets the link grouping preference to port channel, specifies the server pool policy qualifications that will be used to qualify the chassis, and commits the transaction:
UCS-A# scope org /
UCS-A /org # scope chassis-disc-policy
UCS-A /org/chassis-disc-policy* # set descr "This is an example chassis discovery policy."
UCS-A /org/chassis-disc-policy* # set link-aggregation-pref port-channel
UCS-A /org/chassis-disc-policy* # commit-buffer
UCS-A /org/chassis-disc-policy #
What to do next
To customize fabric port channel connectivity for a specific chassis, configure the chassis connectivity policy.