<div dir="ltr">... and remember to fix for 1.25 and master....<br></div><div class="gmail_extra"><br><div class="gmail_quote">On 19 November 2015 at 15:40, Menno Smits <span dir="ltr"><<a href="mailto:menno.smits@canonical.com" target="_blank">menno.smits@canonical.com</a>></span> wrote:<br><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex"><div dir="ltr"><div><div><span style="font-family:monospace,monospace"><font face="arial,helvetica,sans-serif">Hi all,<br><br></font></span></div><span style="font-family:monospace,monospace"><font face="arial,helvetica,sans-serif">While testing something completely unrelated today I noticed that the rsyslog worker was continually failing to start for one of the machines in the environment I was using. When I investigated, I found that the root cause was that the worker wasÂ trying to connect to the state servers with an invalid IPv6 address and port combination (I recently enabled IPv6 on my notebook and home network). As you probably know, IPv6 addresses look something like "fe80::fcb3:4ff:fe6c:ecd3" but what you might not have realised is that the correct way to add a port number to a IPv6 address is to use square brackets like this: "[fe80::fcb3:4ff:fe6c:ecd3]:80" (otherwise - due to IPv6 address contraction it is unclear whether the port is the port number or the end of the address). Various Go "net" package functions will return errors if IPv6 address:port pairs are given without the square brackets. <br><br>The rsyslog worker was joining the address to the port like this: fmt.Sprintf("%s:%d", host, port) which works fine for hostnames and IPv4 addresses but does the wrong thing for IPv6 addresses. The right tool for the job is net.JoinHostPort which will do the right thing with all address types.<br><br></font></span></div><span style="font-family:monospace,monospace"><font face="arial,helvetica,sans-serif">I've fixed the rsyslog worker but have found a number of other places in the code that look like they could suffer from the same problem. Given that IPv6 adoption is increasing[1] we need to fix these areas before Juju's users encounter problems when using Juju with IPv6 networks. Here's what I found:<br></font></span><div><div><div><div><div><span style="font-family:monospace,monospace"><br>provider/local/config.go:Â Â Â Â Â Â return fmt.Sprintf("%s:%d", c.bootstrapIPAddress(), c.storagePort())<br>provider/manual/config.go:Â Â Â Â Â return fmt.Sprintf("%s:%d", c.bootstrapHost(), c.storagePort())<br>provider/manual/config.go:Â Â Â Â Â return fmt.Sprintf("%s:%d", c.storageListenIPAddress(), c.storagePort())<br>state/address.go:Â Â Â Â Â Â Â Â Â Â Â Â Â Â newAddrs[i] = fmt.Sprintf("%s:%d", addr, port)<br>state/backups/backups_linux.go: memberHostPort := fmt.Sprintf("%s:%d", args.PrivateAddress, ssi.StatePort)<br>state/backups/restore_test.go:Â c.Assert(dialInfo.Addrs, gc.DeepEquals, []string{fmt.Sprintf("%s:%d", privateAddress, statePort)})<br>state/backups/restore.go:Â Â Â Â Â Â Addrs: []string{fmt.Sprintf("%s:%d", privateAddr, ssi.StatePort)},<br>utils/ssh/ssh_gocrypto.go:Â Â Â Â Â addr: fmt.Sprintf("%s:%d", host, port),<br></span><br></div><div>Can people who are familiar with each of these areas please take a look, fixing and testing when appropriate.<br><br></div><div>And for future work, please remember: just use net.JoinHostPort..<br><br></div><div>- Menno<br></div><div><br>[1] - on the public internet at least: <a href="https://www.google.com/intl/en/ipv6/statistics.html" target="_blank">https://www.google.com/intl/en/ipv6/statistics.html</a><br></div></div></div></div></div></div> </blockquote></div><br></div>