net: TestLookup* failures with "i/o timeout"

[bcmills]

greplogs --dashboard -md -l -e 'FAIL: TestLookup.*\n .*i/o timeout.*(?:.*\n)*FAIL\s+net' --since=2021-01-01

2021-12-15T00:33:55-9d0ca26/netbsd-arm64-bsiegert

--- FAIL: TestLookupHostCancel (14.66s)
    lookup_test.go:962: lookup www.google.com on 192.168.87.1:53: read udp 192.168.87.23:52715->192.168.87.1:53: i/o timeout
FAIL

2021-12-14T21:23:43-fc8ae98/freebsd-arm-paulzhol

--- FAIL: TestLookupCNAME (76.51s)
    lookup_test.go:370: backoff 1s after failure lookup www.iana.org on 192.168.1.253:53: read udp 192.168.5.15:27642->192.168.1.253:53: i/o timeout
    lookup_test.go:370: backoff 5s after failure lookup www.iana.org on 192.168.1.253:53: read udp 192.168.5.15:11002->192.168.1.253:53: i/o timeout
    lookup_test.go:370: backoff 30s after failure lookup www.iana.org on 192.168.1.253:53: read udp 192.168.5.15:49406->192.168.1.253:53: i/o timeout
    lookup_test.go:376: lookup www.iana.org on 192.168.1.253:53: read udp 192.168.5.15:58118->192.168.1.253:53: i/o timeout
--- FAIL: TestLookupDotsWithRemoteSource (31.02s)
    lookup_test.go:660: LookupAddr(8.8.8.8): lookup 8.8.8.8.in-addr.arpa. on 192.168.1.253:53: read udp 192.168.5.15:28987->192.168.1.253:53: i/o timeout (mode=go)
    lookup_test.go:673: LookupCNAME(www.mit.edu, mode=go): lookup www.mit.edu on 192.168.1.253:53: read udp 192.168.5.15:38636->192.168.1.253:53: i/o timeout
    lookup_test.go:660: LookupAddr(8.8.8.8): lookup 8.8.8.8.in-addr.arpa. on 192.168.1.253:53: read udp 192.168.5.15:17754->192.168.1.253:53: i/o timeout (mode=cgo)
FAIL
FAIL	net	172.152s

2021-11-20T01:00:16-be18cd5/darwin-amd64-nocgo

--- FAIL: TestLookupGoogleHost (20.04s)
    lookup_test.go:403: lookup google.com on 8.8.8.8:53: read udp 172.17.20.32:54917->8.8.8.8:53: i/o timeout
--- FAIL: TestLookupGoogleIP (20.03s)
    lookup_test.go:455: lookup google.com. on 8.8.8.8:53: read udp 172.17.20.32:58664->8.8.8.8:53: i/o timeout
--- FAIL: TestLookupHostCancel (21.01s)
    lookup_test.go:954: lookup www.google.com on 8.8.8.8:53: read udp 172.17.20.32:64884->8.8.8.8:53: i/o timeout

2021-11-17T17:04:16-54b9cb8/solaris-amd64-oraclerel

--- FAIL: TestLookupDotsWithRemoteSource (25.10s)
    lookup_test.go:707: LookupSRV(xmpp-server, tcp, google.com): lookup _xmpp-server._tcp.google.com on 129.70.161.2:53: read udp 129.70.161.63:58549->129.70.161.2:53: i/o timeout (mode=cgo)
FAIL
FAIL	net	50.714s

2021-08-23T21:22:58-8157960/openbsd-arm64-jsing

--- FAIL: TestLookupDotsWithRemoteSource (12.00s)
    lookup_test.go:674: LookupCNAME(www.mit.edu, mode=go): lookup www.mit.edu on 10.2.2.254:53: read udp 10.2.2.13:28276->10.2.2.254:53: i/o timeout
FAIL
FAIL	net	69.817s

2021-07-29T15:30:38-70fd4e4/linux-riscv64-jsing

--- FAIL: TestLookupDotsWithRemoteSource (21.38s)
    lookup_test.go:661: LookupAddr(8.8.8.8): lookup 8.8.8.8.in-addr.arpa. on 127.0.0.53:53: read udp 127.0.0.1:44851->127.0.0.53:53: i/o timeout (mode=go)
    lookup_test.go:661: LookupAddr(8.8.8.8): lookup 8.8.8.8: Temporary failure in name resolution (mode=cgo)
FAIL
FAIL	net	82.313s

2021-07-07T20:33:11-186a3bb/linux-s390x-ibm

--- FAIL: TestLookupGoogleHost (20.02s)
    lookup_test.go:404: lookup google.com. on 9.9.9.9:53: read udp 148.100.113.12:49071->9.9.9.9:53: i/o timeout
--- FAIL: TestLookupGoogleIP (20.02s)
    lookup_test.go:456: lookup google.com. on 9.9.9.9:53: read udp 148.100.113.12:36505->9.9.9.9:53: i/o timeout
panic: test timed out after 3m0s

2021-06-28T21:17:28-5385e23/linux-mips64-rtrk

--- FAIL: TestLookupGoogleHost (40.08s)
    lookup_test.go:404: lookup google.com on 10.11.104.32:53: read udp 10.81.110.62:47707->10.11.104.32:53: i/o timeout
--- FAIL: TestLookupGoogleIP (40.08s)
    lookup_test.go:456: lookup google.com on 10.11.104.32:53: read udp 10.81.110.62:52046->10.11.104.32:53: i/o timeout
FAIL
FAIL	net	320.061s

2021-06-22T14:07:22-666315b/openbsd-arm64-jsing

--- FAIL: TestLookupDotsWithRemoteSource (12.31s)
    lookup_test.go:661: LookupAddr(8.8.8.8): lookup 8.8.8.8.in-addr.arpa. on 10.2.2.254:53: read udp 10.2.2.13:31775->10.2.2.254:53: i/o timeout (mode=go)
FAIL
FAIL	net	52.869s

2021-05-03T16:31:10-472f519/linux-s390x-ibm
2021-05-03T16:25:05-d75fbac/linux-s390x-ibm
2021-05-03T16:23:09-7b768d4/linux-s390x-ibm
2021-04-10T01:46:41-52bf14e/linux-amd64-wsl

--- FAIL: TestLookupGoogleHost (10.01s)
    lookup_test.go:404: lookup google.com on 172.24.112.1:53: read udp 172.24.123.145:35967->172.24.112.1:53: i/o timeout
--- FAIL: TestLookupGoogleIP (10.01s)
    lookup_test.go:456: lookup google.com on 172.24.112.1:53: read udp 172.24.123.145:50137->172.24.112.1:53: i/o timeout
FAIL
FAIL	net	50.567s

2021-03-30T23:56:09-606e0ab/linux-s390x-ibm

--- FAIL: TestLookupDotsWithRemoteSource (107.85s)
    lookup_test.go:661: LookupAddr(8.8.8.8): lookup 8.8.8.8.in-addr.arpa. on 9.9.9.9:53: read udp 148.100.113.12:43600->9.9.9.9:53: i/o timeout (mode=go)
    lookup_test.go:682: LookupMX(google.com): lookup google.com on 9.9.9.9:53: no such host (mode=go)
    lookup_test.go:695: LookupNS(google.com): lookup google.com on 9.9.9.9:53: read udp 148.100.113.12:36256->9.9.9.9:53: i/o timeout (mode=go)
    lookup_test.go:708: LookupSRV(xmpp-server, tcp, google.com): lookup _xmpp-server._tcp.google.com on 9.9.9.9:53: no such host (mode=go)
    lookup_test.go:661: LookupAddr(8.8.8.8): lookup 8.8.8.8.in-addr.arpa. on 9.9.9.9:53: read udp 148.100.113.12:59168->9.9.9.9:53: i/o timeout (mode=cgo)
panic: test timed out after 3m0s

2021-03-30T21:20:51-e0ce0af/linux-s390x-ibm
2021-03-25T04:06:37-c69515c/darwin-amd64-nocgo

--- FAIL: TestLookupHostCancel (15.84s)
    lookup_test.go:955: lookup www.google.com on 8.8.8.8:53: read udp 10.50.0.227:60709->8.8.8.8:53: i/o timeout
FAIL
FAIL	net	36.017s

2021-01-26T00:02:15-ce8b318/netbsd-arm64-bsiegert

[bcmills]

Marking as release-blocker for Go 1.18 via #11811: these failures occur frequently in the builders, and most of them can be addressed by suitable application of testenv.SkipFlaky.

[gopherbot]

Change https://golang.org/cl/372216 mentions this issue: net: skip Lookup tests of external hosts on builders with flaky networks

[gopherbot]

Change https://golang.org/cl/372294 mentions this issue: dashboard: mark builders with unreliable DNS as flaky

[bcmills]

This release-blocking issue is awaiting review of CL 372294 and perhaps a corresponding coordinator redeploy (CC @golang/release).

[toothrot]

The coordinator has been deployed. Closing (until proven otherwise!)

[bcmills]

Looks like we need to mark two more builders with FlakyNet (CC @bsiegert). I'll send a CL.

greplogs -l -e 'FAIL: TestLookup.*\n .*i/o timeout.*(?:.*\n)*FAIL\s+net' --since=2022-01-20
2022-05-30T21:23:29-af88fb6/netbsd-arm64-bsiegert
2022-05-28T20:07:28-52f68ef/netbsd-arm64-bsiegert
2022-05-27T21:36:06-70d499c/netbsd-arm64-bsiegert
2022-05-25T16:16:01-4e4db1e/netbsd-arm64-bsiegert
2022-05-20T19:01:40-69b412b/netbsd-arm-bsiegert
2022-04-29T01:00:55-e7b0559/netbsd-arm64-bsiegert
2022-04-06T17:10:45-9535031/netbsd-arm-bsiegert

[gopherbot]

Change https://go.dev/cl/409474 mentions this issue: dashboard: mark netbsd-arm-bsiegert and netbsd-arm64-bsiegert with FlakyNet