The logfileconfig system test intermittently exhibits several different
failure modes, i.a. on Ubuntu [1], Solaris [2] and OpenBSD [3].

[1] https://jenkins.isc.org/view/BIND/job/bind9-master-ubuntu1604-amd64/440/
[2] https://jenkins.isc.org/view/BIND/job/bind9-master-solaris10-sparc/708/
[3] https://jenkins.isc.org/view/BIND/job/bind9-master-openbsd61-64/184/