There is a DNS resolution bug in Kubernetes (UDP response packets get dropped by conntrack, causing timeouts in DNS queries).
The recommended workaround on Linux is to configure the resolver to use TCP for DNS queries, by setting the use-vc option in resolv.conf.
With this PR, the pure Go resolver searches for "use-vc" in resolv.conf and switches to TCP when found.
Fixes#29358
Change-Id: I26b935cae2c80e5bb9955da83299a8dea84591de
GitHub-Last-Rev: 70bc00fe41
GitHub-Pull-Request: golang/go#29594
Reviewed-on: https://go-review.googlesource.com/c/go/+/156366
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
There is a DNS resolution issue in Kubernetes (UDP response packets get dropped due to a race in conntrack between the parallel A and AAAA queries, causing timeouts in DNS queries).
A workaround is to enable single-request / single-request-reopen in resolv.conf in order to use sequential A and AAAA queries instead of parallel queries.
With this PR, the pure Go resolver searches for "single-request" and "single-request-reopen" in resolv.conf and send A and AAAA queries sequentially when found.
Fixes#29644
Change-Id: I906b3484008c1b9adf2e3e9241ea23767e29df59
GitHub-Last-Rev: d481acfb4c
GitHub-Pull-Request: golang/go#29661
Reviewed-on: https://go-review.googlesource.com/c/go/+/157377
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
BIND libresolv allows values from 0 to 15.
For invalid values and negative numbers, 0 is used.
For numbers greater than 15, 15 is used.
Fixes#15419
Change-Id: I1009bc119c3e87919bcb55a80a35532e9fc3ba52
Reviewed-on: https://go-review.googlesource.com/24901
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Fixes the darwin/arm builder, which has a special test runner which
makes the assumption that tests never use testdata from another
package.
This looks large, but it's no more space in git.
Change-Id: I81921b516443d12d21b77617d323ddebedbe40f8
Reviewed-on: https://go-review.googlesource.com/21907
Reviewed-by: David Crawshaw <crawshaw@golang.org>
Run-TryBot: David Crawshaw <crawshaw@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Parsing literal IPv6 address with zone identifier is already supported
when not using cgo. This change enables it when using cgo too.
Fixes#12241.
Change-Id: I3ed78c9e750e75eff0dae76ba8608df39503cf85
Reviewed-on: https://go-review.googlesource.com/17215
Run-TryBot: Mikio Hara <mikioh.mikioh@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
The previous change for #12806 modified internal lookup tables and made
LookupAddr return forcibly lowercased host names by accident.
This change fixes the issue again without any behavioral change for
LookupAddr and adds missing test cases for lookupStaticHost and
lookupStaticAddr.
Updates #12806.
Fixes#13359.
Change-Id: Ifff4741cd79eb8b320b1b0f8c5e02b3a167c9fa8
Reviewed-on: https://go-review.googlesource.com/17217
Run-TryBot: Mikio Hara <mikioh.mikioh@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
The native Go host resolver was behaving differently than libc
and the entries in the /etc/hosts were handled in a case sensitive
way. In order to be compatible with libc's resolver, /etc/hosts
lookups must be case-insensitive.
Fixes#12806.
Change-Id: I3c14001abffadf7458fd1a027c91e6438a87f285
Reviewed-on: https://go-review.googlesource.com/15321
Run-TryBot: Burcu Dogan <jbd@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
This change fixes incorrect parsing of literal IP addresses in local
database when the addresses contain IPv6 zone identifiers, are in
dotted-decimal notation or in colon-hexadecimal notation with leading
zeros.
https://golang.org/cl/5851 already fixed the code path using getaddrinfo
via cgo. This change fixes the remaining non-cgo code path.
Fixes#8243.
Fixes#8996.
Change-Id: I48443611cbabed0d69667cc73911ba3de396fd44
Reviewed-on: https://go-review.googlesource.com/10306
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
If the machine's network configuration files (resolv.conf,
nsswitch.conf) don't have any unsupported options, prefer Go's DNS
resolver, which doesn't have the cgo & thread over.
It means users can have more than 500 DNS requests outstanding (our
current limit for cgo lookups) and not have one blocked thread per
outstanding request.
Discussed in thread https://groups.google.com/d/msg/golang-dev/2ZUi792oztM/Q0rg_DkF5HMJ
Change-Id: I3f685d70aff6b47bec30b63e9fba674b20507f95
Reviewed-on: https://go-review.googlesource.com/8945
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
jfbus
Katie Hockman
Dan Peterson
Brad Fitzpatrick
Mikio Hara
Burcu Dogan
Russ Cox