Add option ndots:1 to /etc/resolv.conf
This fixes a few issues with DNS queries within docker containers.
Normally when looking up a host name such as "debian.org", libc appends
the search domains from /etc/resolv.conf to the host name, then makes a
separate query for each "long" name. For example, if "search" in
/etc/resolv.conf contains "domain1.org domain2.org", we make 3 queries
when looking for debian.org's IP addr:
- debian.org.domain1.org (fail)
- debian.org.domain2.org (fail)
- debian.org (success)
Setting "ndots:1" makes it send the last unqualified query before the
other queries with appended search domains -- for any names that
contain >= 1 dot.
This patch solves 2 problems:
(1) In Alpine Linux (used by the "docker" pod), libc has a limitation:
the domain search list can't have more than 5 entries. If it does it
stops sending any more DNS queries and the last (unqualified) query
never happens, so many hostname lookups fail.
(2) These extra queries are not necessary a lot of the time, so this
patch makes host name lookups faster
TESTS
===============================
- Rebuild all containers
- Rebuild packages and the ISO
- Make sure DNS queries work in all containers
Story: 2009897
Task: 45156
Signed-off-by: Davlet Panech <davlet.panech@windriver.com>
Change-Id: I7dd72b8fcc776821138c362c3aec9f4e5962a319
ec39ac4d95