Remove limit of one IP address per A record, modify Task.IPs behavior…

[drewkerrigan]

… to return only IPs from first populated source

Addresses #541

• Added second network_infos to a task in factories/fake.json
• Added corresponding test in records/generator_test.go
• Removed ipsTo4And6 in records/generator.go, it was unnecessarily limiting IP lists to a single ipv4 and ipv6 address for no good reason other than to perhaps avoid creating A records for more than one source
• Modified behavior of Task.IPs in records/state/state.go such that it returns all ip addresses from the first populated configured source
  • The previous behavior was to return all available IP addresses from all configured sources. These additional IPs were never used, because the list was always limited to a single ipv4 and ipv6 address.
• Updated a test in records/state/state_test.go to pass with the new Task.IPs behavior

[drewkerrigan]

To test the changes, I've uploaded binaries here: https://github.com/drewkerrigan/mesos-dns/releases/tag/v0.7.1

[f1-outsourcing]

Drew I will ask support to have a look at this.

[jkoelker]

Technically not a problem, but lulz. ;)

[drewkerrigan]

The network name? That's actually the real default ipv6 network name in dcos :-) https://github.com/dcos/dcos/blob/270cb17ec173dc52e69892c1c3ba796414f46936/gen/calc.py#L1140

[jkoelker]

Right, but that's not an ipv6 address ;)

[drewkerrigan]

Whoops, missed that!

[jkoelker]

Howdy! Thanks for taking care of this. It LGTM, but as I'm not 100% on the ramifications on other parts of DC/OS I asked internally for peeps to let me know by 2300 UTC on Wednesday if they see an issue with multiple addresses. From a DNS/Networking POV, it totes makes sense, but just want to make sure there aren't issues that we'll need to shake out elsewhere before incorporating it. If I dont' hear anything back I'll merge it on Wednesday. Happy Hacking!

[f1-outsourcing]

Howdy! Thanks for taking care of this. It LGTM, but as I'm not 100% on the ramifications on other parts of DC/OS I asked internally for peeps to let me know by 2300 UTC on Wednesday if they see an issue with multiple addresses. From a DNS/Networking POV, it totes makes sense, but just want to make sure there aren't issues that we'll need to shake out elsewhere before incorporating it. If I dont' hear anything back I'll merge it on Wednesday. Happy Hacking!

This is an issue[1] I have noticed, but since (I guess) most dcos users do not seem to use multiple ip's, this should not be much of an issue.

[1]
#554