ixfr system test fails intermittently

Two different failure modes, both seem to be related to timing at first glance:

S:ixfr:Thu Feb 15 19:54:14 UTC 2018
T:ixfr:1:A
A:System test ixfr
I:testing initial AXFR
server reload successful
I:testing successful IXFR
zone refresh queued
I:testing AXFR fallback after IXFR failure
zone refresh queued
I:testing ixfr-from-differences option
server reload successful
I:failed to get incremental response
I:testing request-ixfr option in view vs zone
I: this result should be AXFR
server reload successful
I: this result should be AXFR
I:  success: AXFR it was
I: this result should be IXFR
server reload successful
I:  success: IXFR it was
I:testing DiG's handling of a multi message AXFR style IXFR response
I:test 'dig +notcp ixfr=<value>' vs 'dig ixfr=<value> +notcp' vs 'dig ixfr=<value>'
I:exit status: 1
R:FAIL
E:ixfr:Thu Feb 15 19:54:51 UTC 2018

S:ixfr:Thu Feb 15 23:40:59 UTC 2018
T:ixfr:1:A
A:System test ixfr
I:testing initial AXFR
server reload successful
I:testing successful IXFR
zone refresh queued
I:testing AXFR fallback after IXFR failure
zone refresh queued
I:testing ixfr-from-differences option
server reload successful
I:testing request-ixfr option in view vs zone
I: this result should be AXFR
server reload successful
I: this result should be AXFR
I:failed to get nonincremental response in 2nd AXFR test
I: this result should be IXFR
server reload successful
I:  success: IXFR it was
I:testing DiG's handling of a multi message AXFR style IXFR response
I:test 'dig +notcp ixfr=<value>' vs 'dig ixfr=<value> +notcp' vs 'dig ixfr=<value>'
I:exit status: 1
R:FAIL
E:ixfr:Thu Feb 15 23:41:29 UTC 2018

I grabbed the test artifacts from all the jobs listed above lest they get removed.

Edited Feb 16, 2018 by Michał Kępień

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