[Bug 1895418] Re: systemd-resolved default config for Caching is still "yes"

[Launchpad Bug Tracker]

This bug was fixed in the package systemd - 246.6-1ubuntu1

---------------
systemd (246.6-1ubuntu1) groovy; urgency=medium

  [ Dan Streetman ]
  * Fix resolved.conf Cache= default to match default (LP: #1895418)
    Files:
    - debian/patches/lp1895418.patch
    https://git.launchpad.net/~ubuntu-core-dev/ubuntu/+source/systemd/commit/?id=dd4d93d94ebe2cf416f6b5a5eb59a16432cbc47b

  [ Balint Reczey ]
  * Bugfix-only upload
  * Merge from Debian unstable
    - core: propagate unit start limit hit state to triggering path unit (LP: #1891657)
  * Skip test_rsyslog in s390x containers.
    The test is failing almost all the time. (LP: #1895576)
    File: debian/tests/boot-and-services
    https://git.launchpad.net/~ubuntu-core-dev/ubuntu/+source/systemd/commit/?id=ff8d286de52daa8b0856213ae52e66b81474fb57
  * debian/tests/tests-in-lxd: Don't create the lxd test image twice
    File: debian/tests/tests-in-lxd
    https://git.launchpad.net/~ubuntu-core-dev/ubuntu/+source/systemd/commit/?id=e858e7c41b84bc4c34e8af79d6e4b6114fe23952

systemd (246.6-1) unstable; urgency=medium

  * New upstream version 246.6
  * Rebase patches

 -- Balint Reczey <rbalint at ubuntu.com>  Thu, 24 Sep 2020 21:27:11 +0200

** Changed in: systemd (Ubuntu Groovy)
       Status: Fix Committed => Fix Released

-- 
You received this bug notification because you are a member of Ubuntu
Foundations Bugs, which is subscribed to systemd in Ubuntu.
https://bugs.launchpad.net/bugs/1895418

Title:
  systemd-resolved default config for Caching is still "yes"

Status in systemd package in Ubuntu:
  Fix Released
Status in systemd source package in Focal:
  In Progress
Status in systemd source package in Groovy:
  Fix Released

Bug description:
  [impact]

  /etc/systemd/resolved.conf file indicates the default value for
  'Cache=' is 'yes', but the actual default is 'no-negative'

  [test case]

  $ grep Cache /etc/systemd/resolved.conf 
  #Cache=yes

  [regression potential]

  any regression would likely result in a mismatch between the commented
  default value of the Cache parameter and the actual build-time default
  value, or possibly a problem while systemd-resolved is parsing the
  resolved.conf file.

  [scope]

  this is needed only in focal.

  this was changed already in groovy as indicated in comment 1.

  bionic and earlier still use 'yes' as the default value of Cache=,
  which matches the resolved.conf file.

  [original description]

  Back in December, the default for systemd-resolved caching in Ubuntu
  systemd was changed to "no-negative" from the upstream default "yes"
  [0]

  In this change, the default value in the resolved.conf file was
  missed. As the defaults in this file are commented, the effective
  default is still "no-negative", however when viewing the config file,
  the commented default "yes" is at odds with the man page
  resolved.conf(5), which correctly states the default as "no-negative".

  This was an issue for me as I set DNSSEC to "yes", and expected
  Caching to also be "yes". Running DNSSEC with the default "no-
  negative" Caching is detrimental to performance resolving unsigned
  zones, as the non-existence of DNSSEC RRs must be looked up every
  time.

  The issue with the intersection of DNSSEC and Caching is for upstream,
  but the least that needs to be done here is updating the resolved.conf
  template with "Caching=no-negative" to match the man page and
  behaviour, and perhaps even adding a note to the "DNSSEC=" section of
  resolved.conf(5) that Caching should be enabled. Now that I'm looking
  at that man page, the default for DNSSEC is also listed as "allow-
  downgrade", whereas the default for Ubuntu is "no".

  [0] https://git.launchpad.net/~ubuntu-core-
  dev/ubuntu/+source/systemd/commit/?id=b42658843a9496d6b6bb68ac159f2a9f0a8ba9db&h
  =ubuntu-focal

To manage notifications about this bug go to:
https://bugs.launchpad.net/ubuntu/+source/systemd/+bug/1895418/+subscriptions