Wired Intelligent Edge

Hello,

We would like to upgrade our current firmware of HPE 5412R zl2 (with 2 management modules) to a newer version and we would like to do this with the minimum amount of downtime. I've checked the documentation and they mention a reboot of the switch, does this mean rebooting both management modules?

Further is it possible to upgrade the firmware on the standby management module and then make this management module active? And do the same for the management module that was active?

If anyone could point me into the right direction where this is mentioned in the documentation i would be extremely grateful 

Kind regards,

Topd

Is your HP 5412R zl2 management modules redundancy configured for Nonstop-Switching or Warm-Standby (default)?

Thank you for the reply, we are using Nonstop-Switching.

If I've understood correctly what is written on the HPE ArubaOS-Switch Management and Configuration Guide K/KA/KB.16.02 (November 2016) at Appendix A "Chassis Redundancy (HPE 5400R Switches)", "Hotswapping Management Modules" paragraph (page 721), at some point an example [*] (see steps 1 to 8) of "Other software version mismatch conditions" sub-paragraph that can happen is described...reading that example (IMHO not diretly related to Hotswapping in a MM into a Switch)...it seems that you will end up with a system that has one AMM/MM2 (former SMM/MM2) finally running - after a Warm-Start procedure - with the updated software version and the other MM (the former one AMM/MM1 that can be manually forced with a redundancy switchover to boot from the updated flash image) that reboots into the new software assuming the SMM/MM1 role.

So, in the end you will have the AMM/MM2 and SMM/MM1 (standby)...does it means that you will have a downtime? probably yes because then, on the "About downlading a new software version" paragraph there are two sub-paragraphs "File synchronization after downloading" and "Potential software version mismatches after downloading", about the first you can read:

"After installing the new software to the active management module, wait a few minutes, and then verify that the standby management module has been synchronized with the new software as well (use the show flash command.) If the default flash for boot is set correctly, you can start the standby management module on the new software by executing the boot standby command. This does not interrupt current switch operations yet. After the standby management module has rebooted and is ready for takeover in standby mode (you can verify this using the show redundancy command.) you can now switch over to the management module running the newer software with this command:

HP Switch# redundancy switchover

This causes a switchover to the management module that received the new software version, which becomes the active management module. This method incurs the least amount of network downtime for booting. If downtime is not an issue, use the boot system command. Both management modules are then running the new software version."

[*] which describes the behavior when a new software image is installed in secondary flash of the AMM and a redundancy switchover command is executed.

Also, I think, the same conclusion was accepted as solution - hope not to be wrong here - many years ago on a discussion related to a similar case using older HP ProCurve 8200zl Switch.

Will be interesting to see if other users have experience on that too...

OTOH it seems that measured downtime during a software upgrade (downtime during which there is a L2 switching interruption/packets loss) is, as reported by a 2015 Miercom comparison report (http://miercom.com/pdf/reports/20150313.pdf), very low (in the hundreds of milliseconds region) [*]...

[*] clearly if you will be hit by that downtime when your switch is serving high traffic (high pps rate)...half a second of downtime...could mean a lot of packets lost...in comparison of very few milliseconds.

The report gives a good insight on the downtime and i find the HPE documentation a little vague on this part, but you've been a great help! Thank you alot.

Kind Regards,

Topd

Yep, definitely not like ISSU on some Comware switches.

As you, I would have expected to find such simple question already deeply answered using a clear language without generating more doubts than it tries to dispel and, as you, I think available documentation seems to be a little bit lacking or vague about this subject (As example, I would have expected to find - somewhere - a sort of best practices guide describing in detail all the possible procedures/cases for software upgrade when both types of MM redundancies - Nonstop Switching and Warm Standby - are used for cases when very low downtime is the most important factor).

Just reading 

http://miercom.com/pdf/reports/20150313.pdf

I think their comparison is poorly done: they have tested the throughput on a 1-U Cisco 4500 card against a 1/2-U HP card.

The comparison *should* be:
1x Cisco card (1U in the chassis) = 12 ports, 4 groups of 3 ports - each group max 12Gb, max 48Gb for the U, average max 4Gb per 10Gb port
2x HP card = 16 ports, 4 groups of 4 ports - each group max 23Gb, max 94Gb for the U, average max 6Gb per 10Gb port.

Essentially, the HP is 50% superior in terms of over-subscription.

Then they also get port density wrong, by not mentioning the rackspace each uses:
the Cisco supports 80 10Gb ports using 14U, 40 of them at Line Rate
the HP supports 96 10Gb ports using 7U, 48 of them at Line Rate

Then, they mention the 4510 can use VSS to create a 2-chassis pair.
They FAIL to mention you can use VSF to do the same thing with the 5412.

The HP delivers 20% MORE ports, 20% MORE at Line Rate, in ONE HALF the rackspace.

In terms of density and throughput, this document severely downplays the large advantages that the HP switch has over the 4510.

The issue of the much smaller buffers on the HP switch is a big difference. The 5412 is not a datacentre switch. As an Access switch, it is far superior to the Cisco in every relevant respect, and we haven't even spoken of cost. Off the top of my head, I would say the 5412 is half the price of the 4510.

Hi @Vince-Whirlwind: the reference I made above about that Miercom Comparison Report, I underline it here to dispel any possible present and future doubt, was about to provide only a reference about a measured Failover time, personally I don't care (nor I didn't) about that report's result at all (exactly because, as you pointed out, such comparisons aren't exactly a "like-for-like"...IMHO).

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Vince-Whirlwind wrote: Then, they mention the 4510 can use VSS to create a 2-chassis pair.

They FAIL to mention you can use VSF to do the same thing with the 5412.

To be correct you we should recognize and admit that in June 2015, when that report was probably first published, the upcoming VSF technology (disclosed in late 2015 then released in early 2016 with ArubaOS-Switch 16.01 branch) wasn't ever announced yet by HPE/Aruba for their 5400R zl2 Switch series.

Personally I tend to agree with you about all other points you pointed out.