* plugin.md updates
Talk about return code, logging and other bits.
Also checked the code for fmt.Printf logging, there is none.
Fixes#1449#1450
* review
* more typos
* move flag blacklisting to main
Doing it in init() is the wrong place or something else changed. Doing
it in main() makes it easy to see *when* this happens.
* keep trapsignals
* plugin/forward: add out of tree forward plugin
This is a simpler proxy than *proxy*, include by default so it is easier
to switch (i.e. no recompile). It lacks features compared to proxy (did I
say it was simpler), but does cache udp and tcp connection, so it is
faster than proxy.
* Muck with the makefile
* Versioning forward now
* Fix truncation of messages longer than permitted by the client
CoreDNS currently doesn't respect the maximum response size advertised
by the client and returns the full answer on a message with the TC bit
set. This breaks client implementations which rely on DNS servers
respecting the advertised size limit, for example the Ruby stdlib
client. It also has negative network performance implications, as large
messages will be split up into multiple UDP packets, even though the
client will discard the truncated response anyway.
While RFC 2181 permits the response of partial RRSets, finding the
correct number of records fitting into the advertised response size is
non-trivial. As clients should ignore truncated messages, this change
simply removes the full RRSet on truncated messages.
* Remove incorrect etcd test assertion
If a client requests a TXT record larger than its advertised buffer
size, a DNS server should _not_ respond with the answer, but truncate
the message and set the TC bit, so that the client can retry using TCP.
Fix the error handling. Log when we have an error during any of the
transfer state. And if there isn't an error transfer the zones.
Also fix the tests in test/ so we, at least, check the initial transfer.
Update the docs to show more about how errors are handled.
Ref #1400
* plugin/dnssec: filter bitmap also for NXDOMAIN responses
We change nxdomain to nodata, so at the point when we receive the
reply it can be nxdomain or nodata. In both cases we should filter the
nsec bitmap.
Change the code and add explicit tests for this.
* More tests
* plugin/health: add lameduck mode
Add a way to configure lameduck more, i.e. set health to false, stop
polling plugins. Then wait for a duration before shutting down. As the
health middleware is configured early on in the plugin list, it will
hold up all other shutdown, meaning we still answer queries.
* Add New
* More tests
* golint
* remove confusing text
* plugin/dnssec: check validityperiod of RRSIGs
Somehow we missed implementing this. If a sig a retrieved from the
cache, but not valid anymore, regenerate it instead of server invalid
signatures.
Fixes#1378
* drop from cache after 3/4 validity
* six days means 6 days
* Improve plugin/cache metrics
* Add coredns_cache_prefetch_total metric to track number of prefetches.
* Remove unnecessary Cache.get() call which would incorrectly increment
cache counters.
* Initialize all counters and gauges at zero.
* Allow prefetching of a single request per ttl
The original implementation didn't allow prefetching queries which are
only requested once during the duration of a TTL. The minimum amount of
queries which had to be seen was therefore capped at 2.
This change also implements a real prefetch test. The existing test was
a noop and always passed regardless of any prefetch implementation.
* Fix prefetching for items with a short TTL
The default prefetch threshold (percentage) is 10% of the lifetime of a
cache item. With the previous implementation, this disabled prefetching
for all items with a TTL < 10s (the resulting percentage would be 0, at
which point a cached item is already discarded).
This change uses a time based threshold calculation and ensures that
a prefetch is triggered at a TTL of 1 at the latest.
* Fix wrong duration reporting of cached responses
The logging and metrics plugins (among others) included the duration of
a cache prefetch in the request latency of client request. This change
fixes this wrong reporting and executes the prefetch request in a
goroutine in the background.
This fix is an enhancement of external plugin enabling.
Previously, it was already able to build a customerized
coredns with plugins enabled selectively, without changing
coredns source code. However, all default plugins are
actually bundled because of the import rule:
```
"github.com/coredns/coredns/coremain"
```
The issue is best described with the following:
```
root@localhost:/go/src/github.com/coredns/coredns/sample# cat sample.go
package main
import (
_ "github.com/coredns/forward"
"github.com/coredns/coredns/coremain"
"github.com/coredns/coredns/core/dnsserver"
)
var directives = []string{
"forward",
"startup",
"shutdown",
}
func init() {
dnsserver.Directives = directives
}
func main() {
coremain.Run()
}
root@localhost:/go/src/github.com/coredns/coredns/sample#
root@localhost:/go/src/github.com/coredns/coredns/sample# go build -v sample.go
root@localhost:/go/src/github.com/coredns/coredns/sample# ./sample -plugins
root@localhost:/go/src/github.com/coredns/coredns/sample# ./sample -plugins
Server types:
dns
Caddyfile loaders:
flag
default
Other plugins:
dns.auto
dns.autopath
dns.bind
dns.cache
dns.chaos
dns.debug
dns.dnssec
dns.dnstap
dns.erratic
dns.errors
dns.etcd
dns.federation
dns.file
dns.forward
dns.health
dns.hosts
dns.kubernetes
dns.loadbalance
dns.log
dns.nsid
dns.pprof
dns.prometheus
dns.proxy
dns.reverse
dns.rewrite
dns.root
dns.route53
dns.secondary
dns.template
....
```
This fix moves zplugins.go to a different package/directory so that
it is possible to "only import plugins as needed".
The following is the new output after this fix:
```
root@localhost:/go/src/github.com/coredns/coredns/sample# ./sample -plugins
Server types:
dns
Caddyfile loaders:
flag
default
Other plugins:
dns.forward
dns.prometheus
shutdown
startup
root@localhost:/go/src/github.com/coredns/coredns/sample#
```
Signed-off-by: Yong Tang <yong.tang.github@outlook.com>
* Update vendor
Signed-off-by: Yong Tang <yong.tang.github@outlook.com>
* Add route53 plugin
This fix adds route53 plugin so that it is possible to
query route53 record through CoreDNS.
Signed-off-by: Yong Tang <yong.tang.github@outlook.com>
The original ServergRPC.Listen() method returns a tls.Listener
when tls protocol is specified. Unfortunate, tls.Listener
does not implement the caddy.Listener interface that is
needed for graceful restart to work.
The change is to have the ServergRPC.Listen() method returns the
inner net.Listener instead. The creation of the tls.Listener
is deferred to the ServergRPC.Serve() method.
The cache plugin always returned a minimum TTL of 5 seconds, regardless
of the actual TTL of the records. A cache is not authoritative for the
record TTL and should not extend it.
The changes in this fix have:
1. checkout master branch of dependencies (non-branch will trigger an error with go get -u)
2. go get -u
3. checkout specific versioon (not necessary a branch).
Signed-off-by: Yong Tang <yong.tang.github@outlook.com>
This fix fixes version fetched from `go get` so
that versions are guarded.
github.com/mholt/caddy v0.10.10
github.com/miekg/dns v1.0.3
github.com/prometheus/client_golang v0.8.0
golang.org/x/net release-branch.go1.9 (branch)
golang.org/x/text e19ae1496984b1c655b8044a65c0300a3c878dd3
This fix fixes 1368.
Signed-off-by: Yong Tang <yong.tang.github@outlook.com>
* plugin/health: add 'overloaded metrics'
Query our on health endpoint and record (and export as a metric) the
time it takes. The Get has a 5s timeout, that, when reached, will set
the metric duration to 5s. The actually call "I'm I overloaded" is left
to an external entity.
* README
* golint and govet
* and the tests
