There are a bunch of things to test/check/keep in mind when it comes to the upgrade to Varnish 4. Let's collect them in this subtask.
[ ] figure out if varnish4 still has the problem that old VCL shared object continue to consume memory
[ ] remember to use std.ip() instead of ipcast.ip() while porting VCL code
[ ] check if varnishlog and varnishncsa are properly started by puppet
[ ] vmod-tbf sucked at startup time: "at daemon start, everyone's already at the limit". fix the module code and/or our parameter input to make sure we err on the lax side with ratelimits on fresh start
[ ] figure out how to make sure vmod-tbf deallocates the ip db memory on VCL reload