Upgrading from 15.05 to 19.07 broke DHCP on my router?

I've been running 15.05 on my TL-WN1043ND now for quite a while and decided to upgrade to 19.07. Everything seemed to be working correctly, but it turns out the DHCP server wasn't. My setup has 5 internal LANs (br-lan, eth0.3, eth0.4, eth0.5 and eth0.6).

br-lan and eth0.4 have the DHCP server disabled (there is another DHCP server for these networks). eth0.3, 5 and 6 have the DHCP server enabled. This works fine in 15.05 but when I upgraded to 19.07 the DHCP server failed to run (no error or any clear indication why it wasn't).

Is there something different about 19.07 that caused this and if so, how do I fix it?

Did you keep settings when you upgraded? It is it recommended to do so when upgrading across major versions, let alone a jump of 3 releases. That may be exposing some incompatible elements in the configuration you are using and this not functioning as expected.

I did keep the settings during the upgrade ( I even got a backup of the configuration before the upgrade just to be safe). Oddly enough, if I jump back to 15.05 everything works again, just fine. Would it be more prudent to jump through every major version between 15.05 and 19.07?

Running an almost 6 year old firmware version, while vulnerabilities have been discovered and long since patched. :man_facepalming: I have news for you, your security policy needs some work.

The most prudent option would be to reset the router to the default configuration and then recreate the settings via uci, luci, or configuration file edits (if you know the appropriate syntax)

1 Like

no, don't upgrade to reach release incrementally, but as @psherman recommended, wipe to default settings and rebuild your configuration.

upgrading across major versions of openwrt has never worked smoothly for me.

Thanks all for the help. Found the issue - user dnsmasq did not exist in the 15.05 version which caused dnsmasq to not start up in 19.07 (so no dhcp server). I used useradd to add said user to the group, rebooted router and everything is working!

Totally understand - although in my case it's really JUST a router (wifi is disabled as are a lot of other features), http configuration is only accessible from the localhost, etc. Honestly, it's kind of just been running all this time - only reason this came up is because I wanted to verify that the back up unit would work just fine and I figured maybe time to upgrade.

Just to give you a glimpse of past openwrt security vulnerabilities

https://www.cvedetails.com/vulnerability-list/vendor_id-18578/Openwrt.html

This topic was automatically closed 10 days after the last reply. New replies are no longer allowed.