I've updated the test case on this, which from what people are saying,
should make it easier to reproduce.

I've yet to sort out the debdiff on this for yakkety, I'll be sorting
that out later today.

** Description changed:

  sssd in both xenial and yakkety fails to update the PTR record of the
  current host on an active directory controller if any update for an
  A/AAA record returns a non-fatal error, this results in missing (and/or)
  mismatched Reverse DNS.
  
  This has already been fixed in 1.5.1 (which is present in Zesty and
  above), as failure to update any of the A/AAA should not affect updating
  the PTR as well, as not all servers in a given AD cluster may accept an
  A/AAA record update, especially if it would result in no update being
  made (NOERROR).
  
  See the attached conversation about this issue here:
  https://pagure.io/SSSD/sssd/issue/3227 for further information.
  
  I'll attach a debdiff against the relevant releases shortly, however for
  now I've attached the original patch which was used to fix the bug in
  1.15.1
  
  ### SRU Justification ###
  
  [Impact]
  
  Currently users find that sssd will not update the reverse (PTR) records
  of a given host if an AD server returns non-fatal error for an A/AAA
  update.
  
  This causes strange issues to occur where we can end up with hosts with
  proper functioning forward records but no reverse. I propose we backport
  the fix from 1.15.1 to both Xenial and Yakkety to resolve the issue so
  PTR updates get processed (or at least attempted).
  
  The patch attached removes the error check that occurs should the return
  code of the A/AAA nsupdates be non zero, and instead allows the PTR
  update to occur before checking for errors.
  
  This is the same patch taken from the fix for 1.15.1
  
  [Test Case]
  
- As per the original bug:
+ For the configuration of sssd, a basic configuration of the following
+ should suffice:
  
- Steps to Reproduce:
- 1. Setup 'nonsecure and secure' zones
- 2. Start sssd
+ [sssd]
+ services = nss, pam
+ config_file_version = 2
+ domains = YOURDOMAIN.TLD
  
- Actual results:
- A records will get updated but PTR records will fail as sssd does not try to
- update them.
+ [domain/YOURDOMAIN.TLD]
+ id_provider=ad
+ auth_provider=ad
+ access_provider=ad
+ chpass_provider=ad
+ override_homedir=/home/%d/%u
+ cache_credentials = true
+ ad_gpo_access_control=permissive
+ default_shell=/bin/bash
+ ad_hostname = sssd-hostname.YOURDOMAIN.TLD
+ 
+ In AD change the properties of the Forward zone Dynamic Updates to  
"Nonsecure and Secure"
+ Ensure a Reverse Zone is present in the AD DNS MMC.
+ Remove any existing A/AAAA and PTR records from Active Directory DNS for the 
SSSD system
+ Restart SSSD to trigger the nsupdate call
+ Check the reverse zone in AD for PTR records, they do not get created but the 
A/AAAA records do.
  
  Expected results:
  Both A and PTR records get updated.
  
  [Regression Potential]
  
  As this patch is already present in a future release it has been fairly
  well tested already however back-porting the fix will result in sssd
  attempting PTR updates whether the A/AAA updates succeeds or not.
  
  As per the original bug report where a quick note was made about failed
  updates; If forward updates fail the result will be inconsistent DNS
  should the reverse succeed (reverse but no forward), however in that
  case the admin needs to look into with why the update failed, the code
  should at least try to record all updates (both A, AAA and PTR) and not
  just ignore the PTR because the forward update (may or may not have)
  failed.
  
  There is also the possibility that the patch may not resolve the problem
  completely however as this patch just moves the error handling before
  the PTR attempt I can see no reason not to backport the patch to the
  older version for Xenial/Yakkety.

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https://bugs.launchpad.net/bugs/1706284

Title:
  sssd fails to Update PTR if any A record update fails.

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