Upgrade WRT3200ACM from 19.07 to 21.02.3

[richb-hanover-priv]

I'm looking for the best practice for an upgrade for my WRT3200ACM from 19.07.8 to the newest (21.02.3) release. I know there were some considerations back in the RC-x days, and maybe these have been fixed. I've seen two problems mentioned:

• You cannot keep settings, because networking has changed (DSA). @hnyman mentioned a workaround in Linksys WRT3200ACM & 21.02.0-RC1 popup message - #7 by hnyman

• There was some issue with the flash layout with early versions, but I have seen fragmentary information that makes me think that more recent versions automatically address this.

My questions:

1. Do the items above address the problems?
2. Are there other problems with upgrading?

That is, can I simply download the SYSUPGRADE image from the Firmware Selector and use LuCI to flash it, as long as I don't keep settings? (Or if I rename the network and system config files as suggested by @hnyman?)

I want to get this right because this router is in production, and I have a narrow maintenance window. (And of course, I will take a backup before making any changes.) Thanks!

[hnyman]

Sysupgrading should work ok, as long as you remove the network and system config files.

(Wrt3200acm did not have kernel partition size problems. Wrt32x did have.)

Ps. due to the dual firmware, you will always have the current 19.07 partition as the fallback, in any case.

[richb-hanover-priv]

@hnyman

Ps. due to the dual firmware, you will always have the current 19.07 partition as the fallback, in any case.

@hnyman OK. I'm feeling a little dopey, but I couldn't find a clear explanation of how to switch back to the fallback partition on the wiki or in the forum...

Would someone post a link? (This is router-specific, so refer to the links in the next post.) Thanks

[hnyman]

@richb-hanover-priv

I couldn't find a clear explanation of how to switch back to the fallback partition on the wiki

The advice from wiki:

• https://openwrt.org/toh/linksys/wrt3200acm#firmware_recovery
• https://openwrt.org/toh/linksys/wrt_ac_series#firmware_recovery

Please don't add that to the generic failsafe/recovery page, as it is specific to the Linksys dual-boot routers.

[richb-hanover-priv]

Once again, Thanks!

[richb-hanover-priv]

@hnyman I had trouble finding the page you linked to when I searched. I think part of the problem is that the heading is "Firmware Recovery". But that gets hidden by/confused with "Recovery Mode" on the Failsafe, Reset, Recovery page.

Most of the posts I read use the term "fallback". Would it be correct to change the heading to Dual Firmware Fallback and the text on that page to something like:

Dual Firmware Fallback

This router supports two firmware partitions. If the firmware has become unresponsive and won't boot, chances are you can recover it easily due to this Dual Firmware partition layout, by switching falling back to the alternate firmware partition.

For this reason, it is recommended to always keep at least one known good version of the firmware on either partition.

You can switch from primary to alternate partition or vice versa using any of the 4 below methods: ...etc...

Update: s/dual partition fallback/dual firmware fallback/g