Bug 42529 – Reduce complexity in the GPO sysvol share access

Bug 42529 - Reduce complexity in the GPO sysvol share access


Summary:	Reduce complexity in the GPO sysvol share access

Status:	RESOLVED WONTFIX

Product:	UCS
Classification:	Unclassified
Component:	Samba4
Version:	UCS 4.2
Hardware:	Other Linux

Importance:	P5 enhancement (vote)
Target Milestone:	---
Assigned To:	Samba maintainers
QA Contact:

URL:
Keywords:

Depends on:
Blocks:
	Show dependency tree / graph

Reported:	2016-09-28 16:30 CEST by Arvid Requate
Modified:	2020-07-03 20:53 CEST (History)
CC List:	1 user (show)

See Also:	39674
What kind of report is it?:	Feature Request
What type of bug is this?:	---
Who will be affected by this bug?:	---
How will those affected feel about the bug?:	---
User Pain:
Enterprise Customer affected?:
School Customer affected?:
ISV affected?:
Waiting Support:
Flags outvoted (downgraded) after PO Review:
Ticket number:
Bug group (optional):	Troubleshooting
Max CVSS v3 score:

Attachments
Add an attachment (proposed patch, testcase, etc.)

Note You need to log in before you can comment on or make changes to this bug.

Description Arvid Requate

2016-09-28 16:30:44 CEST

GPO management and evaluation from a Windows client can run into temporary issues because

1. of the way we synchronize the sysvol (not instantaneous)
2. the Windows client gets a round robin IP address when looking up domainname to acces //domainname/sysvol
3. Samba/AD additionally sends a randomized DFS referal to the Windows client

We should think about a way to improve the situation. This is purely on the file level of GPOs. For LDAP operations the GPMC tool chooses the PDC emulator (FSMO role, usually the DC Master), only the file related side of this makes things so twisted. Point 3 above is hardcoded in Samba, adjusting that would require a patch.

Comment 1 Arvid Requate

2016-09-28 16:48:06 CEST

One (crazy,creative,largely untested) idea as a workaround would be to add another level of indirection (the "fundamental theorem of software engineering"):

=====================================================================
## First disable sysvol sync &cleanup on all DCs.
ucr set samba4/sysvol/sync/cron='# */5 * * * *'
ucr set samba4/sysvol/cleanup/cron='# 4 4 * * *'

## On all DCs but the DC Master (not on the DC Master!!) do the following steps:

## Then activate "msdfs root" for sysvol
echo -e "[sysvol]\n\tmsdfs root = yes\n" >> /etc/samba/local.conf
ucr commit /etc/samba/smb.conf
/etc/init.d/samba restart

## and link to the master:
eval "$(ucr shell)"
mv "/var/lib/samba/sysvol/$domainname" \
   "/var/lib/samba/sysvol/$domainname.OFF"
ln -s msdfs:"$ldap_master\\sysvol\\$domainname" \
   "/var/lib/samba/sysvol/$domainname"
=====================================================================

Comment 2 Ingo Steuwer

2020-07-03 20:53:07 CEST

This issue has been filed against UCS 4.2.

UCS 4.2 is out of maintenance and many UCS components have changed in later releases. Thus, this issue is now being closed.

If this issue still occurs in newer UCS versions, please use "Clone this bug" or reopen it and update the UCS version. In this case please provide detailed information on how this issue is affecting you.