Retry edns512 multiple times to trigger fallback to edns at 512

We want named to have slow resolving (multiple retries) when
there is a very small working MTU
76 jobs for !4295 with 2230-legacy-system-test-fails-intermittently in 16 minutes and 54 seconds (queued for 8 seconds)
detached
Status Job ID Name Coverage
  Autoconf
passed #1246514
amd64 linux
autoreconf

00:00:17

 
  Precheck
passed #1246516
amd64 linux
clang-format

00:00:16

passed #1246517
amd64 linux
coccinelle

00:03:43

passed #1246518
amd64 linux
danger

00:00:14

passed #1246515
amd64 linux
misc

00:00:16

passed #1246519
amd64 linux
tarball-create

00:01:49

 
  Build
passed #1246532
amd64 linux
clang:asan

00:02:01

passed #1246536
amd64 linux
clang:buster:amd64

00:01:10

passed #1246539
amd64 libvirt
clang:freebsd11:amd64

00:01:11

passed #1246540
amd64 libvirt
clang:freebsd12:amd64

00:01:11

passed #1246541
amd64 libvirt
clang:openbsd:amd64

00:02:27

passed #1246534
amd64 linux
clang:tsan

00:01:17

passed #1246520
amd64 linux
gcc:alpine3.12:amd64

00:01:02

passed #1246531
amd64 linux
gcc:asan

00:01:48

passed #1246524
amd64 linux
gcc:buster:amd64

00:00:46

passed #1246521
amd64 linux
gcc:centos7:amd64

00:00:58

passed #1246522
amd64 linux
gcc:centos8:amd64

00:00:49

passed #1246530
amd64 linux
gcc:focal:amd64

00:01:11

passed #1246535
amd64 linux
gcc:mutexatomics

00:01:00

passed #1246526
amd64 linux
gcc:out-of-tree

00:01:02

passed #1246525
amd64 linux
gcc:sid:amd64

00:01:00

passed #1246527
i386 linux
gcc:sid:i386

00:01:03

passed #1246537
amd64 linux
gcc:softhsm2.4

00:00:50

passed #1246538
amd64 linux
gcc:softhsm2.6

00:01:02

passed #1246523
amd64 linux
gcc:stretch:amd64

00:01:08

passed #1246533
amd64 linux
gcc:tsan

00:01:08

passed #1246528
amd64 linux
gcc:tumbleweed:amd64

00:01:02

passed #1246529
amd64 linux
gcc:xenial:amd64

00:01:06

passed #1246542
amd64 windows
msvc:windows:amd64

00:01:51

 
  Unit
passed #1246554
amd64 linux
unit:clang:asan

00:01:15

passed #1246558
amd64 linux
unit:clang:buster:amd64

00:01:03

passed #1246561
amd64 libvirt
unit:clang:freebsd11:amd64

00:01:30

passed #1246562
amd64 libvirt
unit:clang:freebsd12:amd64

00:01:25

passed #1246563
amd64 libvirt
unit:clang:openbsd:amd64

00:02:49

passed #1246556
amd64 linux
unit:clang:tsan

00:03:04

passed #1246543
amd64 linux
unit:gcc:alpine3.12:amd64

00:00:58

passed #1246553
amd64 linux
unit:gcc:asan

00:01:12

passed #1246547
amd64 linux
unit:gcc:buster:amd64

00:02:02

passed #1246544
amd64 linux
unit:gcc:centos7:amd64

00:00:59

passed #1246545
amd64 linux
unit:gcc:centos8:amd64

00:01:04

passed #1246552
amd64 linux
unit:gcc:focal:amd64

00:00:58

passed #1246557
amd64 linux
unit:gcc:mutexatomics

00:01:00

passed #1246548
amd64 linux
unit:gcc:sid:amd64

00:01:05

passed #1246549
i386 linux
unit:gcc:sid:i386

00:01:10

passed #1246559
amd64 linux
unit:gcc:softhsm2.4

00:00:59

passed #1246560
amd64 linux
unit:gcc:softhsm2.6

00:00:58

passed #1246546
amd64 linux
unit:gcc:stretch:amd64

00:01:02

passed #1246555
amd64 linux
unit:gcc:tsan

00:03:52

passed #1246550
amd64 linux
unit:gcc:tumbleweed:amd64

00:00:55

passed #1246551
amd64 linux
unit:gcc:xenial:amd64

00:01:00

 
  System
passed #1246575
amd64 linux
system:clang:asan

00:13:11

passed #1246579
amd64 linux
system:clang:buster:amd64

00:11:06

passed #1246582
amd64 libvirt
system:clang:freebsd11:amd64

00:10:19

passed #1246583
amd64 libvirt
system:clang:freebsd12:amd64

00:10:41

passed #1246577
amd64 linux
system:clang:tsan

00:14:30

passed #1246564
amd64 linux
system:gcc:alpine3.12:amd64

00:12:10

passed #1246574
amd64 linux
system:gcc:asan

00:13:12

passed #1246568
amd64 linux
system:gcc:buster:amd64

00:12:40

passed #1246565
amd64 linux
system:gcc:centos7:amd64

00:11:03

passed #1246566
amd64 linux
system:gcc:centos8:amd64

00:11:32

passed #1246573
amd64 linux
system:gcc:focal:amd64

00:11:30

passed #1246578
amd64 linux
system:gcc:mutexatomics

00:10:46

passed #1246569
amd64 linux
system:gcc:sid:amd64

00:10:46

passed #1246570
i386 linux
system:gcc:sid:i386

00:11:06

passed #1246580
amd64 linux
system:gcc:softhsm2.4

00:10:50

passed #1246581
amd64 linux
system:gcc:softhsm2.6

00:11:32

passed #1246567
amd64 linux
system:gcc:stretch:amd64

00:10:56

passed #1246576
amd64 linux
system:gcc:tsan

00:14:49

passed #1246571
amd64 linux
system:gcc:tumbleweed:amd64

00:11:07

passed #1246572
amd64 linux
system:gcc:xenial:amd64

00:10:24

 
  Docs
passed #1246584
amd64 linux
docs

00:00:35

 
  Postcheck
passed #1246588
amd64 linux
cppcheck

00:00:44

passed #1246585
amd64 linux
flake8

00:00:21

passed #1246589
amd64 linux
gcov

00:00:32

77.0%
passed #1246586
amd64 linux
pylint

00:00:22

passed #1246587
amd64 linux
scan-build

00:04:23