Upgrade but no upgrade path (because DSA, R7800)

[mdzprocter]

Device name: Netgear Nighthawk X4S R7800
Architechture: ARMv7 Processor rev 0 (v7l)
Target platform: ipq806x/generic

Hello I haven't been using my OpenWRT router for over a year and today I have reactivated it. It still has OpenWRT 22.03.2 on it and it's working fine, but I would like to upgrade at some point, so looked up the Release notes for OpenWrt 24.10.0 and they warned me that for the ipq806x platform there is no upgrade path, you cannot preserve configuration.

But what does that mean? Do I have to re-configure everything or is there an easier way, for example edit the backup file and throw out some files, ie. /etc/config/network (the default switch config will be fine) Other files I need to be aware of? So what's the best procedure here?

Regarding the switch config I really didn't change anything, just the rest of the systems have a ton of customizations: port forwardings, static routes, dns server configs, dyndns, rrd tool and more, so I would like to avoid setting everything up from scratch.

Thanks in advance

[badulesia]

@mdzprocter

Do I have to re-configure everything

Yes.
backup your settings
Instal 23.05, as upgrading from 22.03 to 24.10 is not officially supported. than install 24.10. DO NOT keep settings while upgrading as config files need to be new due to DSA. Do not try to restore the settings using the file, it will brick your device.
Once done, you may use your old backup file to handly pick some settings such as MAC adresses, password.

[mdzprocter]

Is it possible that under some circumstances an upgrade from non-DSA to DSA it can migrate the configuration by itself? I upgraded a device using sysupgrade and I believe the release notes said it was not supported but it worked anyway.

[hnyman]

@mdzprocter

Do I have to re-configure everything or is there an easier way, for example edit the backup file and throw out some files, ie. /etc/config/network (the default switch config will be fine) Other files I need to be aware of?

With R7800's DSA change, you can keep most config files, but not those that refer directly to interface names or to switch ports. Network, system, SQM, ...

I have jumped back and forth by just removing those three files before sysupgrade. (I actually keep the old swconfig based config files for 23.05 that I can put into correct place before sysupgrade)

R7800: upgrade 23.05.4 -> 24.10.0

The config breaking change there is the swconfig-->DSA switch config systax migration. You can likely sysupgrade keeping all other config files than /etc/config/network, system (and sqm), which directly refer to network hardware. I have been jumping from/to 23.05 due to my R7800 community build, and I have kept alternate versions of those three, and just renamed the correct version to be the actual before sysupgrade. Old advice in You can get the new defaults by simply removing (or renamin…

Build for Netgear R7800

22.03 is so long ago, that hard to remember. But I do not think that there was anything major between 22.03 and 23.05. For the DSA change after 23.05 to 24.10 and onward, the needed changes depend quite much from for network complexity. With a simple network, the only files are network (actual DSA changes) and system (compatibility value and wan LED config). In addition the config files for those apps that refer to interfaces by name. E.g. for me sqm refers to eth0.2 , which needs now to be wa…

[mdzprocter]

You can keep most config files, but not those that refer directly to interface names or to switch ports. Network, system, SQM, ...

Thank you for your in-depth answers. I will give it a try. One more thing, this seems like a weird question but should I use sysupgrade or is it "cleaner" to flash the factory image via tftp?

[hnyman]

There is no difference in functionality.
With factory you can't naturally keep any config, and selectively restoring backups can be difficult.
So, I would use sysupgrade but remove network and system config.

Ps. One additional thing: even if the dsa/swconfig migration would soft-brick the wired connection, it has no impact to wireless, which still works.

[mdzprocter]

@hnyman

With R7800's DSA change, you can keep most config files, but not those that refer directly to interface names or to switch ports. Network, system, SQM, ...

Thank you so much, it worked like a charm! From 23 to 24 I did throw out these 3 files and reconfigured these via LuCi. Here's my experience with it (maybe something to watch out for for the next guy)

• When repackaging the configuration tarball with the wrong permissions, so some applications, including dropbear wouldn't work right with the wrong permissions. After chowning everything back to root on the device (yikes), it worked.
• I forgot since I threw out the network config, I had to go back to Network, Interfaces and change the IP.
• The SQM configuration confused me a bit, but now it seems to work OK. It receives A+ grading on waveform which is great for the time being. If I remember correctly it used to be a bit better (0 jitter) but I'll figure that out later.

[hnyman]

@mdzprocter

SQM configuration confused me a bit

For sqm the only needed change would have likely been just the interface name, likely from 'eth0.2' to 'wan'.

[hnyman]

@mdzprocter

From 23 to 24 I did throw out these 3 files and reconfigured these via LuCi. Here's my experience with it (maybe something to watch out for for the next guy)

• When repackaging the configuration tarball with the wrong permissions, so some applications, including dropbear wouldn't work right with the wrong permissions. After chowning everything back to root on the device (yikes), it worked.

Regarding that, one more hint for the next guy...

Instead of deleting them from the backup archive, you could have either

• deleted them in the live router before making the backup, so that you don't have to manipulate the backup archive itself, or alternatively
• renamed them to 'network.swconfig' etc., so that the 'netowrk' config file is not found during the boot, but the file is there for reference (or for going back to the old version).