* Allow server TLS configuration to be reloaded via SIGHUP
* dynamic tls reloading for nomad agents
* code cleanup and refactoring
* ensure keyloader is initialized, add comments
* allow downgrading from TLS
* initalize keyloader if necessary
* integration test for tls reload
* fix up test to assert success on reloaded TLS configuration
* failure in loading a new TLS config should remain at current
Reload only the config if agent is already using TLS
* reload agent configuration before specific server/client
lock keyloader before loading/caching a new certificate
* introduce a get-or-set method for keyloader
* fixups from code review
* fix up linting errors
* fixups from code review
* add lock for config updates; improve copy of tls config
* GetCertificate only reloads certificates dynamically for the server
* config updates/copies should be on agent
* improve http integration test
* simplify agent reloading storing a local copy of config
* reuse the same keyloader when reloading
* Test that server and client get reloaded but keep keyloader
* Keyloader exposes GetClientCertificate as well for outgoing connections
* Fix spelling
* correct changelog style
This PR allows tuning of heartbeat TTLs. An example of very aggressive
settings is as follows:
```
server {
heartbeat_grace = "1s"
min_heartbeat_ttl = "1s"
max_heartbeats_per_second = 200.0
}
```
A fix to #2739 instead of forcing IPv6 users to always specify a port as
well.
Prior to this commit IPv6 advertise addresses which lacked a port would
fail instead of having the default port added because
`net.SplitHostPort(someipv6)` returns a different error than
`net.SplitHostPort(someipv4)`.
A slight improvement to #2399 - if bind is localhost, return an error
instead of advertising a private ip. The advertised ip isn't valid and
will just cause errors on use. It's better to fail with an error message
instructing users how to fix the problem.
This PR:
* Uses Go 1.8 executable lookup
* Stores any err message from stats init method
* Allows overriding of Cpu Compute for hosts where it can't be detected
This PR introduces a parallelism limit during garbage collection. This
is used to avoid large resource usage spikes if garbage collecting many
allocations at once.