Re: [go-nuts] go1.11 no longer supports compressed hostnames in SRV lookup replies
On Friday, September 7, 2018 at 5:43:24 AM UTC+9, Jason Newman wrote: > > I pinged a couple of people associated with kube-dns and they were able to > reproduce the issue on the latest kube-dns release (1.14.10). They are > planning on tagging a new release of kube-dns that includes an improvement > to the behavior. Thank you all for the guidance. > can you please fine an issue in the go issue tracker too? the issue, especially regarding dns-sd, is a real issue and could be a roadblock in near future. thanks. -- You received this message because you are subscribed to the Google Groups "golang-nuts" group. To unsubscribe from this group and stop receiving emails from it, send an email to golang-nuts+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/d/optout.
Re: [go-nuts] go1.11 no longer supports compressed hostnames in SRV lookup replies
I pinged a couple of people associated with kube-dns and they were able to reproduce the issue on the latest kube-dns release (1.14.10). They are planning on tagging a new release of kube-dns that includes an improvement to the behavior. Thank you all for the guidance. On Friday, August 31, 2018 at 1:13:45 AM UTC-6, mikioh...@gmail.com wrote: > > On Friday, August 31, 2018 at 2:54:08 PM UTC+9, Jason Newman wrote: >> >> Is it worth creating an issue around this? We have extracted the DNS >> client from `net` and are currently using it with the compressed flag >> enabled to allow compressed hostnames - the behavior that existed in go >> 1.10 and earlier. >> > > sure, please file an issue, at least we need to discuss how to deal > with srv rrs not only for classical unicast dns but for the latest unicast > dns, multicast dns and dns-sd, though there's no guarantee that the > previous wrong behavior will be back in future releases. > > for the record: > - in rfc2782, "... name compression is not to be used for this field." > - in rfc6762, "One specific difference between Unicast DNS and Multicast > DNS is that ... all Multicast DNS implementations are REQUIRED to decode > compressed SRV records correctly." > - in rfc6763, "Using DNS name compression ..." > > unfortunately, the dns specifications are everybody's friend; it's hard > to tame, to make a one-fits-all solution for the specs. > >> -- You received this message because you are subscribed to the Google Groups "golang-nuts" group. To unsubscribe from this group and stop receiving emails from it, send an email to golang-nuts+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/d/optout.
Re: [go-nuts] go1.11 no longer supports compressed hostnames in SRV lookup replies
On Friday, August 31, 2018 at 2:54:08 PM UTC+9, Jason Newman wrote: > > Is it worth creating an issue around this? We have extracted the DNS > client from `net` and are currently using it with the compressed flag > enabled to allow compressed hostnames - the behavior that existed in go > 1.10 and earlier. > sure, please file an issue, at least we need to discuss how to deal with srv rrs not only for classical unicast dns but for the latest unicast dns, multicast dns and dns-sd, though there's no guarantee that the previous wrong behavior will be back in future releases. for the record: - in rfc2782, "... name compression is not to be used for this field." - in rfc6762, "One specific difference between Unicast DNS and Multicast DNS is that ... all Multicast DNS implementations are REQUIRED to decode compressed SRV records correctly." - in rfc6763, "Using DNS name compression ..." unfortunately, the dns specifications are everybody's friend; it's hard to tame, to make a one-fits-all solution for the specs. > -- You received this message because you are subscribed to the Google Groups "golang-nuts" group. To unsubscribe from this group and stop receiving emails from it, send an email to golang-nuts+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/d/optout.
Re: [go-nuts] go1.11 no longer supports compressed hostnames in SRV lookup replies
We have traced the issue to the Kubernetes DNS server, kube-dns. It is
returning compressed hostnames in SRV query responses. It can be reproduced
by running
The following app exits with an error in MiniKube (or any other Kubernetes
cluster with kube-dns).
cannot unmarshal DNS message - Target: compressed name in SRV resource data
func main() {
_,_, err := net.LookupSRV("dns-tcp", "tcp", "kube-dns.kube-system")
if err != nil {
log.Fatal(err)
}
}
Is it worth creating an issue around this? We have extracted the DNS client
from `net` and are currently using it with the compressed flag enabled to
allow compressed hostnames - the behavior that existed in go 1.10 and
earlier.
On Wednesday, August 29, 2018 at 4:57:04 PM UTC-6, Jason Newman wrote:
>
> This code works in our Kubernetes cluster when compiled with Go 1.10 and
> does not work when compiled with Go 1.11, we are using the built-in Go
> resolver.
>
> https://play.golang.org/p/JNSJEm1n6hg
>
> On Wednesday, August 29, 2018 at 4:28:54 PM UTC-6, Nathan Fisher wrote:
>>
>> Can you share examples?
>> On Wed, Aug 29, 2018 at 19:08, wrote:
>>
>>> We are using SRV records in Kubernetes for various purposes and Go 1.11
>>> no longer supports compressed names in SRV resource data (
>>> https://github.com/golang/net/commit/24dd3780ca4f75fed9f321890729414a4b5d3f13#diff-47e2241916c7047eab73daf76c89fc3fR2055).
>>>
>>> The error we are getting is "cannot unmarshal DNS message" and the
>>> underlying error is "Target: compressed name in SRV resource data".
>>>
>>> Ultimately, we believe the issue lies with dnsmasq returning a
>>> non-compliant SRV response, but it is stopping us from upgrading to Go1.11.
>>> Are there any known workarounds which would allow us to handle these
>>> noncompliant SRV responses?
>>>
>>>
>>>
>>>
>>> --
>>> You received this message because you are subscribed to the Google
>>> Groups "golang-nuts" group.
>>> To unsubscribe from this group and stop receiving emails from it, send
>>> an email to golang-nuts...@googlegroups.com.
>>> For more options, visit https://groups.google.com/d/optout.
>>>
>> --
>> - sent from my mobile
>>
>
--
You received this message because you are subscribed to the Google Groups
"golang-nuts" group.
To unsubscribe from this group and stop receiving emails from it, send an email
to golang-nuts+unsubscr...@googlegroups.com.
For more options, visit https://groups.google.com/d/optout.
Re: [go-nuts] go1.11 no longer supports compressed hostnames in SRV lookup replies
This code works in our Kubernetes cluster when compiled with Go 1.10 and does not work when compiled with Go 1.11, we are using the built-in Go resolver. https://play.golang.org/p/JNSJEm1n6hg On Wednesday, August 29, 2018 at 4:28:54 PM UTC-6, Nathan Fisher wrote: > > Can you share examples? > On Wed, Aug 29, 2018 at 19:08, > > wrote: > >> We are using SRV records in Kubernetes for various purposes and Go 1.11 >> no longer supports compressed names in SRV resource data ( >> https://github.com/golang/net/commit/24dd3780ca4f75fed9f321890729414a4b5d3f13#diff-47e2241916c7047eab73daf76c89fc3fR2055). >> >> The error we are getting is "cannot unmarshal DNS message" and the >> underlying error is "Target: compressed name in SRV resource data". >> >> Ultimately, we believe the issue lies with dnsmasq returning a >> non-compliant SRV response, but it is stopping us from upgrading to Go1.11. >> Are there any known workarounds which would allow us to handle these >> noncompliant SRV responses? >> >> >> >> >> -- >> You received this message because you are subscribed to the Google Groups >> "golang-nuts" group. >> To unsubscribe from this group and stop receiving emails from it, send an >> email to golang-nuts...@googlegroups.com . >> For more options, visit https://groups.google.com/d/optout. >> > -- > - sent from my mobile > -- You received this message because you are subscribed to the Google Groups "golang-nuts" group. To unsubscribe from this group and stop receiving emails from it, send an email to golang-nuts+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/d/optout.
Re: [go-nuts] go1.11 no longer supports compressed hostnames in SRV lookup replies
Can you share examples? On Wed, Aug 29, 2018 at 19:08, wrote: > We are using SRV records in Kubernetes for various purposes and Go 1.11 no > longer supports compressed names in SRV resource data ( > https://github.com/golang/net/commit/24dd3780ca4f75fed9f321890729414a4b5d3f13#diff-47e2241916c7047eab73daf76c89fc3fR2055). > The error we are getting is "cannot unmarshal DNS message" and the > underlying error is "Target: compressed name in SRV resource data". > > Ultimately, we believe the issue lies with dnsmasq returning a > non-compliant SRV response, but it is stopping us from upgrading to Go1.11. > Are there any known workarounds which would allow us to handle these > noncompliant SRV responses? > > > > > -- > You received this message because you are subscribed to the Google Groups > "golang-nuts" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to golang-nuts+unsubscr...@googlegroups.com. > For more options, visit https://groups.google.com/d/optout. > -- - sent from my mobile -- You received this message because you are subscribed to the Google Groups "golang-nuts" group. To unsubscribe from this group and stop receiving emails from it, send an email to golang-nuts+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/d/optout.
[go-nuts] go1.11 no longer supports compressed hostnames in SRV lookup replies
We are using SRV records in Kubernetes for various purposes and Go 1.11 no longer supports compressed names in SRV resource data (https://github.com/golang/net/commit/24dd3780ca4f75fed9f321890729414a4b5d3f13#diff-47e2241916c7047eab73daf76c89fc3fR2055). The error we are getting is "cannot unmarshal DNS message" and the underlying error is "Target: compressed name in SRV resource data". Ultimately, we believe the issue lies with dnsmasq returning a non-compliant SRV response, but it is stopping us from upgrading to Go1.11. Are there any known workarounds which would allow us to handle these noncompliant SRV responses? -- You received this message because you are subscribed to the Google Groups "golang-nuts" group. To unsubscribe from this group and stop receiving emails from it, send an email to golang-nuts+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/d/optout.
