Migrating to Cisco UCS 6500 Series Fabric Interconnects

Cisco UCS 6400 Series Fabric Interconnect Migration

Cisco UCS 6400 Series Fabric Interconnect Migration Considerations

Beginning with Cisco UCS Manager, Release 4.3(2b), You can migrate Cisco UCS 6400 Series Fabric Interconnects to Cisco UCS 6536 Fabric Interconnect with B-Series servers, C-Series, or S-Series servers.

To migrate from Cisco UCS 6400 Series Fabric Interconnects to Cisco UCS 6536 Fabric Interconnect:

  • Cisco UCS 6400 Series Fabric Interconnects must be on Cisco UCS Manager 4.3(2b) or a later release.

  • Cisco UCS 6536 Fabric Interconnect must be loaded with the same Infrastructure Firmware version that is on the Cisco UCS 6400 Series Fabric Interconnect that it will replace.

Prerequisites

Before performing the migration from Cisco UCS 6400 Series Fabric Interconnects to Cisco UCS 6536 Fabric Interconnect, ensure that the following prerequisites are met for a successful migration:

  • Back up and export Cisco UCS Manager configuration before initiating the upgrade.

  • Take an inventory of the Cisco UCS domain and remove any unsupported hardware.

  • Ensure to enable the cluster failover.

  • Do not attempt to implement new software features from the new Cisco UCS software version until all required hardware is installed.

  • Validate the software features and configurations between Cisco UCS 6400 series and UCS 6536 Fabric Interconnects. Before migration, ensure that 6400 series Fabric Interconnect is reconfigured to only have features that are supported with 6536 Fabric Interconnects.


    Note

    This is one of the most common reasons for migration failures.

  • Make sure both Cisco UCS 6400 series and 6500 series Fabric Interconnects are on the same UCSM build before migration.

  • Licenses from Cisco UCS 6400 Series Fabric Interconnects are not transferable to Cisco UCS 6500 Series Fabric Interconnects. Cisco UCS 6500 Series Fabric Interconnects has perpetual license enabled by default.

  • Standalone installations should expect down time. In a cluster configuration, migrating the Fabric Interconnects can result in a small traffic disruption when the traffic fails over from one Fabric Interconnect to another. To avoid that there is no permanent traffic loss during migration, ensure that there is redundancy in the UCS domain on both Fabric Interconnects before migration and test the redundancy before starting the migration.

  • Cisco UCS 6536 Fabric Interconnect use the IDLE fill pattern for FC uplink ports and FC storage ports when using 8 Gbps speed.

    When migrating to Cisco UCS 6536 Fabric Interconnect and configuring FC Uplink Ports or FC Storage Ports at 8Gbps speed, ensure that the fill pattern is set as IDLE on the corresponding FC switch ports and the direct-attached FC storage array ports. If the fill pattern is not set as IDLE, FC uplink ports and FC storage ports operating at 8 Gbps might go to an errDisabled state, lose SYNC intermittently, or receive errors or bad packets.

    Cisco UCS 6536 Fabric Interconnects supports 8 Gbps only with fill-pattern set to IDLE for direct-attached FC connectivity (FC uplink ports or FC storage ports). This limitation is not applicable for Cisco UCS 6536 Fabric Interconnects with Fibre Channel (FC) ports at 16 Gbps and 32 Gbps. When migrating to Cisco UCS 6536 Fabric Interconnect for direct-attached storage arrays that don’t support IDLE fill-pattern at 8 Gbps do one of the following:

    • Use a SAN switch between the Cisco UCS 6536 Fabric Interconnect and the storage array with 8 GB FC connectivity.

    • Upgrade the storage array to 16 GB or 32 GB FC connectivity.

  • Ensure the latest firmware bundle is downloaded and upgraded through GUI or CLI. Incase of attempting to upgrade the firmware bundle using other methods (loader prompt/erase configuration) can result in missing package version.

  • Before migration, make sure that the FC Speed is 8Gbps on Cisco UCS 6400 Fabric Interconnects or the connected switch supports 8Gbps speed.


    Note

    Post migration, you can configure the FC Port (Scalability Port) speed on Cisco UCS 6500 Fabric Interconnects.

  • Migrating to different IOM models can result in peer communication issue between IOMs of the Primary and Secondary Fabric Interconnects.

  • Make a detailed record of the cabling between FEX and fabric interconnects. You must preserve the physical port mapping to maintain the server pinning already configured and minimize down time.

  • For a cluster configuration, both fabric interconnects must have symmetrical connection topologies between fabric interconnect and FEX.

  • Use the same speed cables on all the adapter ports that are connected to same Fabric Interconnect. Cisco UCS VIC adapter ports connected to Cisco UCS 6536 fabric interconnect through a mix of 10G and 25G cables can result in UCS rack-mount server discovery failure and ports moving to suspended state.

  • Cisco UCS 6536 Fabric Interconnect only supports 25/40/100G direct connectivity for C-series rack servers and 10G direct-connect is not supported on C-series rack servers. The Cisco UCS 6536 Fabric Interconnect supports 10G server connectivity only with 2348-UPQ FEX.

  • A WWN pool can include only WWNNs or WWPNs in the ranges from 20:00:00:00:00:00:00:00 to 20:FF:00:FF:FF:FF:FF:FF or from 50:00:00:00:00:00:00:00 to 5F:FF:00:FF:FF:FF:FF:FF. All other WWN ranges are reserved. When fibre channel traffic is sent through the UCS infrastructure the source WWPN is converted to a MAC address. You cannot use WWPN pool which can translate to source multicast MAC addresses. To ensure the uniqueness of the Cisco UCS WWNNs and WWPNs in the SAN fabric, Cisco recommends using the following WWN prefix for all blocks in a pool: 20:00:00:25:B5:XX:XX:XX

  • Unconfigure the fibre channel ports on the migrating subordinate Cisco UCS 6400 series Fabric Interconnect and reconfigure on the Cisco UCS 6536 Fabric Interconnect.

Recommendations

Following are the best practices for a successful migration:

  • For minimal disruption during migration, ensure that there is redundancy for Ethernet and FC traffic from the servers in the UCS domain across both 6400 series fabric interconnects before migration.

  • Changes to the topology, such as the number of servers or uplink connections, should be performed after the fabric interconnect migration is complete.

  • During the migration of Fabric Interconnects, ensure the Cluster ID is not changed.

  • During the migration, image synchronization between fabric interconnects is not allowed. This is done to prevent incompatible images from getting synchronized. It is necessary to download B-Series, C-Series, and S-Series server software bundles again after migration is complete.

  • During the migration, ensure that VLAN is not created in the range of 3915 to 4042 which are the reserved VLAN range for Cisco UCS 6536 Fabric Interconnects.

  • The Cisco UCS 6536 Fabric Interconnect supports only port-channel mode for chassis-discovery. Hence, before starting migration, change the chassis/FEX discovery policy on the Cisco UCS 6400 series Fabric Interconnect to port-channel and immediately re-acknowledge the chassis.


    Note

    The migration can fail when the chassis is not immediately re-acknowledged.

Note

For more information on migrating Cisco UCS 6400 series Fabric Interconnects to Cisco UCS 6500 series Fabric Interconnect with UCS Central, see Considerations for migrating Cisco UCS 6400 Series Fabric Interconnects to Cisco UCS 6500 Series Fabric Interconnects with Cisco UCS Central.

Validating Feature Configurations for Cisco UCS 6536 before Upgrade

Cisco UCS 6536 Fabric Interconnect does not support some software features that were allowed with Cisco UCS 6400 Series Fabric Interconnect. Some of these features will become available at a later software release.

Table 1. Features that needs special attention prior to upgrading

Feature

Remediation

License Management

Licensing for Cisco UCS 6536 Fabric Interconnect is not a port-based license like in previous generation Fabric Interconnects.

All ports are enabled through a perpetual license in Cisco UCS 6536 Fabric Interconnect and no license installation is required.

Chassis and fabric extender I/O port channel

Select a port channel to the I/O module (IOM).

Multicast optimization

Verify that multicast optimization is not enabled under the LAN quality-of-service (QoS) system classes

Fabric forwarding mode for Ethernet

Verify that the Ethernet forwarding mode is set to End Host Mode Only.

Fabric forwarding mode for Fibre Channel

Verify that Fibre Channel forwarding mode is set to End Host Mode or FC Switching Mode.

Cisco NetFlow

Unconfigure NetFlow.

MAC Security

Select Allow for MAC security.

VM-FEX

Remove port profiles and Cisco UCS Manager ESXi or SCVMM related configurations.

Dynamic vNIC connection policies

Set the dynamic vNIC connection policy in the vNIC profile to Not set.

Cisco Switched Port Analyzer (SPAN)

Use receive (RX) direction only. The installer will change SPAN to the RX direction and send an alert indicating that this setting is being changed.

Failure to comply with these remediation steps will result in a migration warning alert during the migration process and prevent the fabric interconnects from synchronizing.

Considerations for migrating Cisco UCS 6400 Series Fabric Interconnects to Cisco UCS 6500 Series Fabric Interconnects with Cisco UCS Central

In addition to Cisco UCS 6400 Series Fabric Interconnect Migration Considerations, consider the following prerequisites when migrating with Cisco UCS Central:

  • Before initiating the migration, ensure to have a complete backup of Cisco UCS Manager and UCS Central configurations.

  • To avoid any configuration issues during migration, make sure the following policies on Policy Resolution Control is set to Local in Cisco UCS Manager:

    • Infrastructure and Catalog Firmware Policy

    • Equipment Policy

    • Port Configuration Policy

Migrating from UCS 6400 Series Fabric Interconnects to UCS 6536 Fabric Interconnects

Cisco UCS 6400 Series Fabric Interconnects include Cisco UCS 6454 and Cisco UCS 64108. You can migrate from Cisco UCS 6400 Series Fabric Interconnects to Cisco UCS 6536 Fabric Interconnect. After migrating to Cisco UCS 6536 Fabric Interconnect, Cisco recommends not to migrate back to UCS 6400 Series Fabric Interconnect.

The Cisco UCS 6536 Fabric Interconnect supports only port-channel mode for chassis-discovery. On changing the chassis or FEX discovery policy to port-channel, the chassis needs to be re-acknowledged before proceeding with the migration.

To acknowledge the chassis in Cisco UCS Manager, do the following:

  1. In the Navigation pane of Cisco UCS Manager, click Equipment.

  2. Click the Equipment node.

  3. In the Work pane, click the Policies tab.

  4. Click the Global Policies subtab.

  5. Expand Equipment > Chassis, and choose the chassis that you want to acknowledge.

  6. In the Work pane, click the General tab.

  7. In the Actions area, click Acknowledge Chassis.


Note

For more information about how to perform configuration procedures in Cisco UCS Manager, see the appropriate Cisco UCS Manager Configuration Guide.

Procedure

Step 1

Move the traffic to the primary fabric interconnect. This can be performed in two ways: fabric evacuation and uplink disablement. Use the below flowchart to choose between the two based on your Cisco UCS domain server and connectivity.

Note

 

For direct-attached rack servers, only uplink disablement is supported.

Step 2

Verify that all traffic has failed over to the primary fabric interconnect. Unconfigure all server ports or fibre channel ports on the subordinate fabric interconnect.

For more information, see the Fabric Interconnect Traffic Evacuation section in the Guidelines and Prerequisites chapter of the Cisco UCS Manager Firmware Management Guide.

Step 3

Power down the old subordinate fabric interconnect and disconnect the power and the L1/L2 cables.

If you are monitoring the migration using a KVM session to a server host, you may need to reconnect it after you powered down the secondary fabric interconnect.

Step 4

Mount the replacement Cisco UCS 6536 Fabric Interconnect into either the same rack or an adjacent rack.

Note

 

As a best practice, you should label the cables.

Step 5

Connect the L1/L2 cables and the server ports according to your port mapping plan.

Step 6

Power up the new fabric interconnect. If it is connected correctly, the new subordinate fabric interconnect will detect that it is being added to an existing cluster.

Step 7

The subordinate Cisco UCS 6536 Fabric Interconnect will automatically synchronize the configuration and database/state information from the primary UCS 6400 Series Fabric Interconnect.

Synchronization between primary and subordinate fabric interconnects can take several minutes. You may see an error message that will persist until the server ports are enabled.

The port configuration is copied from the subordinate Fabric Interconnect to the new Fabric Interconnect.

Step 8

Unified ports on the 6500 series fabric interconnect are different from the unified port ordering on the 6400 series Fabric Interconnect.

Note

 

  • When you convert from ethernet ports to fibre channel ports, a reboot is required. Fibre channel ports are converted in blocks of four (breakout ports).

  • For more information on Configuring FC Uplink port or Converting FC storage port to FC uplink port, see the LAN Ports and Port Channels chapter in Cisco UCS Manager Network Management Guide.

Step 9

Configure the network uplink ports on the new Cisco UCS 6536 fabric interconnect.

Step 10

Match the old configuration from Cisco UCS 6400 Fabric Interconnect for the port-channel. Add uplink ports to the necessary port-channel or any other previous configuration required for the port-channel. Wait for configuration to complete before proceeding to the next step.

Note

 

Waiting to enable the server ports prevents the svc_sam_bladeAG service from communicating with chassis and servers. In previous migrations, when enabling server ports at the same time as the uplink ports, it would cause topping out (pinning) the CPU to near 100% on the primary fabric interconnect. When there is high CPU usage, the user interface becomes unresponsive and the svc_sam_bladeAG service must be restarted to recover.

Step 11

Reconfigure the server ports or fibre channel ports.

  1. If you have changed port mappings, you may need to reacknowledge the IOM, FEX, or direct-connect rack server connected to the subordinate fabric interconnect.

  2. Verify and if necessary, you can reconfigure ethernet ports as server ports.

  3. Skip to Step 13 to verify the data path.

Step 12

To remove and replace the new IOM or FEX and reconfigure the server ports, do the following:

  1. Remove the existing IOM connected to the subordinate Fabric Interconnect and replace it with a supported IOM of Cisco UCS 6536 Fabric Interconnect.

  2. Verify if any modifications are required for the cable connections.

  3. Reconfigure the new IOM to maintain the same port mappings. If port mapping were not preserved, configure the server ports accordingly.

  4. Reacknowledge the IOM connected to the subordinate Fabric Interconnect.

Step 13

Verify that the data path is ready.

For more information, see the Verifying that Dynamic vNICs Are Up and Running section in the Guidelines and Prerequisites chapter of the Cisco UCS Manager Firmware Management Guide.

Ensure that all faults are resolved before proceeding with next step.

  1. Verify, and if necessary, reconfigure the SAN pin group for fibre channel ports in the associated service profile.

  2. Verify, and if necessary, reconfigure the LAN pin group for ethernet ports in the associated service profile.

  3. Verify, and if necessary, reconfigure the port channel for uplink ethernet ports.

Step 14

Move the traffic back to the new subordinate fabric interconnect. If you used the fabric evacuation method, then deselect fabric evacuation. If you disabled the uplinks (Ethernet and Fibre Channel), then re-enable the uplinks. Verify that traffic is flowing correctly on the new subordinate fabric interconnect.

Step 15

After verifying that traffic is flowing on the subordinate fabric interconnect, promote the subordinate fabric interconnect to primary using the below commands:

  • UCS-A #connect local-mgmt: This command connects to the local management interface of the cluster.

  • UCS-A (local-mgmt) #cluster{lead {a|b}} or UCS-A (local-mgmt) #cluster{force primary{a|b}}: The cluster lead command and cluster force primary command are two separate commands that can be used for promoting the fabric interconnect.

Note

 

Ensure that the primary fabric interconnect is Cisco UCS 6536 Fabric Interconnect.

Step 16

Cable the second new fabric interconnect identically to the first and repeat the steps for the other fabric interconnect replacements to complete the migration.