Create plugin/pkg/transport that holds the transport related functions.
This needed to be a new pkg to prevent cyclic import errors.
This cleans up a bunch of duplicated code in core/dnsserver that also
tried to parse a transport (now all done in transport.Parse).
Signed-off-by: Miek Gieben <miek@miek.nl>
* plugin/forward: add HealthChecker interface
Make the HealthChecker interface and morph the current DNS health
checker into that interface.
Remove all whole bunch of method on Forward that didn't make sense.
This is done in preparation of adding a DoH client to forward - which
requires a completely different healthcheck implementation (and more,
but lets start here)
Signed-off-by: Miek Gieben <miek@miek.nl>
* Use protocol
Signed-off-by: Miek Gieben <miek@miek.nl>
* Dial doesnt need to be method an Forward either
Signed-off-by: Miek Gieben <miek@miek.nl>
* Address comments
Address various comments on the PR.
Signed-off-by: Miek Gieben <miek@miek.nl>
After several experiments at SoundCloud we found that the current
minimum read timeout of 10ms is too low. A single request against a
slow/unavailable authoritative server can cause all TCP connections to
get closed. We record a 50th percentile forward/proxy latency of <5ms,
and a 99th percentile latency of 60ms. Using a minimum timeout of 200ms
seems to be a fair trade-off between avoiding unnecessary high
connection churn and reacting to upstream failures in a timely manner.
This change also renames hcDuration to hcInterval to reflect its usage,
and removes the duplicated timeout constant to make code comprehension
easier.
Rework the TestProxyClose - close the proxy in the *same* goroutine
as where we started it. Close channels as long as we don't get dataraces
(this may need another fix).
Move the Dial goroutine out of the connManager - this simplifies things
*and* makes another goroutine go away and removes the need for connErr
channels - can now just be dns.Conn.
Also:
Revert "plugin/forward: gracefull stop (#1701)"
This reverts commit 135377bf77.
Revert "rework TestProxyClose (#1735)"
This reverts commit 9e8893a0b5.
* plugin/forward: gracefull stop
- stop connection manager only when no queries in progress
* minor improvement
* prevent healthcheck on stopped proxy
* revert closing channels
* use standard context
