I’m looking at upgrading from 1.8 to 2.0. But I haven’t been able to find if what, if any, the breaking changes are. Is there a list of breaking changes, or an upgrade guide somewhere?
There is no upgrade guide.
I suggest to read the .0 release announcements:
HTX is enabled by default in 2.0, this can have an impact on non-compliant clients and servers/applications (header-names must be case-insensitive and will be lower-cased due to the internal representation). Some checks are stricter due to HTX. The Makefile TARGET becomes
linux-glibc instead of
Those 2 points are the major changes to look out for. Of course adequate testing should be performed before rolling it out.