Migrating IRF Ports

[Stefano Colombo]

Hi all,

I've got a question regarding a possible scenario in which we could need to change the IRF port speed in a 4 member stack

At this time all the 4 members are using 40Gb ports to form the stacks, using DAC cable connecting two switches on each "side" and 40Gb NPO patch cable to connect them "across" the sites.

SW1    ---NPO--   SW3

SW2   ---NPO--  SW4

At this time all the 4 sw are on the same rack but SW3,SW4 should be moved to another rack.
Due to some problem with NPO cabling we're thinking of changing each single NPO connection with a "split" 4x10Gb

So the questions are:

- Can we have an IRF stack with mixed IRF ports where SW1-SW2 and SW3-SW4 are connected with 40Gb DAC and SW1-SW3 and SW2-SW4 are connected with 4x10Gb links ?

- Can we move from actual configuration to the desired one without downtime ?

thanks

[Ivan_B]

HI @Stefano Colombo !

Please, state model number of your switches, some limitations could be applicable, so we need to know exact model.

Output from following commands will be helpful:

display version
display device verbose
display irf configuration

In general, answers would be:

- Can we have an IRF stack with mixed IRF ports where SW1-SW2 and SW3-SW4 are connected with 40Gb DAC and SW1-SW3 and SW2-SW4 are connected with 4x10Gb links ?
- Yes, if there is no hardware limitation for certain platform to use split ports, it should work. You can mix different ports in one IRF, though it is not recommended.

- Can we move from actual configuration to the desired one without downtime ?
- Yes, it is possible. Since SW1 and SW2 have DAC IRF links, they will keep working while SW3 and SW4 being moved to another rack.

[Stefano Colombo]

Hello

here the outputs

MemberID NewID IRF-Port1 IRF-Port2
1 1 FortyGigE1/0/29 FortyGigE1/0/30
2 2 FortyGigE2/0/30 FortyGigE2/0/29
3 3 FortyGigE3/0/30 FortyGigE3/0/29
4 4 FortyGigE4/0/29 FortyGigE4/0/30

HPE Comware Software, Version 7.1.070, Release 2702P01
Copyright (c) 2010-2021 Hewlett Packard Enterprise Development LP
HPE 5710 24XGT 6QS+/2QS28 Switch uptime is 7 weeks, 6 days, 23 hours, 48 minutes
Last reboot reason : Cold reboot

Boot image: flash:/5710-cmw710-boot-r2702p01.bin
Boot image version: 7.1.070, Release 2702P01
Compiled Jan 06 2021 11:00:00
System image: flash:/5710-cmw710-system-r2702p01.bin
System image version: 7.1.070, Release 2702P01
Compiled Jan 06 2021 11:00:00

<SG-BU-SW-SRV> display device verbose
Slot Type State Subslot Soft Ver Patch Ver
1 5710 24XGT 6QS+/ Master 0 2702P01 None
2QS28 Switch
2 5710 24XGT 6QS+/ Standby 0 2702P01 None
2QS28 Switch
3 5710 24XGT 6QS+/ Standby 0 2702P01 None
2QS28 Switch
4 5710 24XGT 6QS+/ Standby 0 2702P01 None
2QS28 Switch

[Ivan_B]

The Virtual Technologies Configuration Guide https://internal.support.hpe.com/hpesc/public/docDisplay?docLocale=en_US&docId=a00078536en_us says the following about IRF port restrictions:

IMPORTANT: Some switch models might not support splitting some QSFP+ or QSFP28 ports to use their breakout interfaces to establish IRF links. To identify these switch models, see the installation guide for the switch series.

Checking the suggested guide https://internal.support.hpe.com/hpesc/public/docDisplay?docLocale=en_US&docId=a00050395en_us reveal following:

You can provide the following IRF physical connections between HPE FlexFabric 5710 switches:
• 10-GE IRF physical connection by connecting 10GBASE-T Ethernet ports or SFP+ ports.
• 40-GE IRF physical connection by connecting QSFP+ ports.
• 100-GE IRF physical connection by connecting QSFP28 ports.
• IRF physical connection by using a 40G QSFP+ to 4 × 10G SFP+ cable to connect a QSFP+ port and four SFP+ ports.
You can bind several ports to an IRF port for increased bandwidth and availability.

Taking these details into account you can split a 40-GE interface into four 10-GE breakout interfaces and use them as IRF ports. The 10-GE breakout interfaces support the same configuration and attributes as common 10-GE interfaces, except that they are numbered differently. For example, you can split 40-GE interface FortyGigE 1/0/1 into four 10-GE breakout interfaces Ten-GigabitEthernet 1/0/1:1 through Ten-GigabitEthernet 1/0/1:4. 

You can use one of these splitter cables:

HPE FlexNetwork X240 40G QSFP+ to 4x10G SFP+ 1m Direct Attach Copper Splitter Cable JG329A
HPE FlexNetwork X240 40G QSFP+ to 4x10G SFP+ 3m Direct Attach Copper Splitter Cable JG330A
HPE FlexNetwork X240 40G QSFP+ to 4x10G SFP+ 5m Direct Attach Copper Splitter Cable JG331A