Fex With vPC and ISSU
Fex With vPC and ISSU
FEX design support with Nexus 70000 and vPC:
Fex is the Fabric Extender and its connection with Nexus 7000 is very limited and on very less line cards.
FEX can be connected to the following parent line cards:
- 32 X 10-Gbps ETH ports line card (N7K-M132XP-12 and N7K-M132XP-12L)
- 24 X 10-Gbps ETH ports line card (N7K-M224XP-23L)
- 48 X 1/10-Gbps ETH ports line card (N7K-F248XP-25, N7K-F248XP-25E, N77-F248XP-23E, N7K-F348XP-25, N77-F348XP-23)
- 6 X 40-Gbps ETH ports line card (N7K-M2406FQ-23L) in native 40G mode and break-out mode
- 12 X 40-Gbps ETH ports line card (N7K-F312FQ-25) in native 40G mode and break-out mode
- 24 X 40-Gbps ETH ports line card (N77-F324FQ-25) in native 40G mode and break-out mode
Models of FEX supported as of NX-OS 6.0 are:
- N2K-C2232PP (32 X 1/10-Gbps fiber Host Interface and 8 X 10-Gbps FEX uplinks)
- N2K-C2248TP-E / N2K-C2248TP-1GE (48 X 100-Mbps/1-Gbps copper Host Interface and 4 X 10-Gbps FEX uplinks)
- N2K-C2224TP / N2K-C2224TP-E (24 X 100-Mbps/1-Gbps copper Host Interface and 4 X 10-Gbps FEX uplinks)
- N2K-C2232TM / N2K-C2232TM-E (32 X 1/10-Gbps copper Host Interface and 8 X 10-Gbps FEX uplinks)
- N2K-C2248PQ (48 X 1/10G Fiber Host Interface and 4 X 40-Gbps FEX uplinks)
- N2K-C2348UPQ (48 X 1/10G Fiber Host Interface and 6 X 40-Gbps FEX uplinks)
- N2K-C2348TQ (48 X 100-Mbps/1/10-Gbps copper Host Interface and 6 X 40-Gbps FEX uplinks)
Following is the sample topology which can be used as reference to connect FEX with Nexus 7000.
All models of FEX (2224, 2248 and 2232) support 8 port-channel member ports max. Total number of member ports in a host vPC configuration can go up to 16. In a host vPC configuration, there is no requirement that both FEX models match on both sides of the vPC. FEX 2224 can be used in the left side and FEX 2248 can be used on the right side for instance.
Host facing ports on FEX can be configured as switch port mode access or switch port mode trunk (so carrying multiple VLAN). Configure these ports as spanning-tree port type edge or edge trunk to force the ports to transition to forwarding state quickly.
Following design are not supported with Fex and vPC on Nexus 7000 NX-OS 6.0
- eVPC (enhanced vPC)
- vPC with 1 leg on FEX and the other leg on NEXUS 7000 line card
vPC & NX-OS Upgrade
vPC feature is fully compatible with Cisco ISSU (In-Service Software Upgrade) or ISSD (In-Service Software Downgrade). A Cisco NX-OS code upgrade (or downgrade) on a vPC system can be performed without any packet loss.In a vPC environment (with or without use of VDC), an ISSU is the recommended method to upgrade the system. The vPC system can be independently upgraded with no disruption to traffic. The upgrade is serialized and must be run one at the time. The configuration lock during ISSU prevents synchronous upgrades on both vPC peer devices to happen (configuration is automatically locked on other vPC peer device when ISSU is initiated).
To perform ISSU operation, 1 single knob is needed. From the default VDC, type the following command:
install all kickstart <bootflash_kickstart-image> system <bootflash_system-image>
vPC presents the advantage to run seamlessly even if the 2 vPC peer devices operate with different NX-OS code.
For instance, vPC peer device 1 can run with NX-OS 5.2 release while the other vPC peer device runs with NX-OS 6.0 code. This is the key to support hitless upgrade for the vPC domain.
In Step 1, as Figure 88 shows, both vPC peer devices run the Release 5.2 code. Release 6.0 code is loaded on vPC peer device 1, 7K1 (loading the code first on primary or secondary vPC peer device has no importance) using ISSU. Note that other vPC peer device (7K2) has its configuration locked to protect against any operation on the switch.
In Step 2, vPC peer device 1 (7K1) is now loaded with NX-OS Release 6.0. vPC peer device 2 (7K2) now loads the Release 6.0 code using ISSU. 7K1 configuration is then locked to prevent any change during the upgrade.During this transition phase, vPC system works fine even if both peer devices have different NX-OS code.
In Step 3, both vPC peer devices run the Release 6.0 code. ISSU process is now completed.