use guard values for testing unixtime serial

(cherry picked from commit abe41ba0)
20 jobs for 424-nsupdate-tests-fail-intermittently-v9_12 in 15 minutes and 15 seconds (queued for 5 seconds)
Status Job ID Name Coverage
  Precheck
passed precheck:debian:sid:amd64 #30437
amd64 docker linux

00:00:11

 
  Build
passed build:centos:centos6:amd64 #30438
amd64 docker linux

00:02:38

passed build:centos:centos7:amd64 #30439
amd64 docker linux

00:02:48

passed build:debian:sid:amd64 #30440
amd64 docker linux

00:01:54

passed build:debian:sid:i386 #30629
linux docker i386

00:01:23

passed build:debian:sid:i386 #30441
i386 docker linux

00:01:57

 
  Test
passed systemtest:centos:centos6:amd64 #30446
amd64 docker linux

00:05:24

passed systemtest:centos:centos7:amd64 #30447
amd64 docker linux

00:05:08

passed systemtest:debian:sid:amd64 #30448
amd64 docker linux

00:05:33

passed systemtest:debian:sid:i386 #30630
i386 docker linux

00:04:35

passed unittest:centos:centos6:amd64 #30442
docker linux amd64

00:00:53

passed unittest:centos:centos7:amd64 #30443
amd64 docker linux

00:00:47

passed unittest:debian:sid:amd64 #30444
amd64 docker linux

00:00:47

passed unittest:debian:sid:i386 #30445
i386 docker linux

00:00:47

failed systemtest:debian:sid:i386 #30628
linux docker i386

00:00:00

failed systemtest:debian:sid:i386 #30614
i386 docker linux

00:00:00

failed systemtest:debian:sid:i386 #30613
linux docker i386

00:00:00

failed systemtest:debian:sid:i386 #30612
i386 docker linux

00:00:00

failed systemtest:debian:sid:i386 #30611
linux docker i386

00:00:00

failed systemtest:debian:sid:i386 #30449
i386 docker linux

00:06:06