Internal dhcp unable to acquire IP from certain routers, breaking network connection for many users

NetworkManager 1.10 introduced a breaking change by making dhcp=internal the default instead of dhclient. Many distros pushed out NM 1.10 obviously without being aware of that change. Lots of users are reporting issues with their wifi connection etc. in support forums and lots of guesswork is happening about what is the cause.

For example, Manjaro pushed 1.10 a few weeks ago then recommended downgrading to 1.8 after users reporting issues. They pushed a few distro upgrades since then without solving the problem for affected users. Manjaro by default installs package dhclient and an empty Networkmanager.conf so package upgrade of networkmanager changes the DHCP client mechanism to internal. I have been affected as well. NM 1.10 is not able to obtain an IP from my Linksys LRT224 router using dhcp=internal, however after a few weeks on a downgraded networkmanager I found out that setting dhcp=dhclient fixes the issue.

I am sure there has been put serious consideration of switching default to dhcp=internal for NM. However, according to the noise in distro support forums there may be quite a number of users affected by this issue. Others may notice this only on occasion e.g. when trying to connect to a public wifi somewhere. Unfortunately I cannot give a list of DHCP server implementations/routers that do not play well with NM internal DHCP client, except of my setup with that particular Linksys model.

I noticed that the change is not mentioned in 1.10 release notes and strongly suggest amending them accordingly. I could only verify the change by comparing man pages of 1.8 vs. 1.10.

As for the general issue of not properly working internal DHCP client: for me the only notable symptom is simple a timeout after 45sec when waiting for an IP. This happens on different machines with different network hardware and on wifi as well as on LAN. I have put my logs on pastebin here:

[Date Prev][Date Next]   [Thread Prev][Thread Next]   [Thread Index] [Date Index] [Author Index]