Bug 36012

Summary:	Warn about hostnames with underscores
Product:	UCS	Reporter:	Janis Meybohm <meybohm>
Component:	UMC - System diagnostic	Assignee:	Lukas Oyen <oyen>
Status:	CLOSED FIXED	QA Contact:	Jürn Brodersen <brodersen>
Severity:	normal
Priority:	P5	CC:	best, gohmann, oyen, requate
Version:	UCS 4.1	Flags:	oyen: Patch_Available+
Target Milestone:	UCS 4.2-2-errata
Hardware:	Other
OS:	Linux
What kind of report is it?:	Feature Request	What type of bug is this?:	---
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Attachments:	36012-diagnostic-hostname-check-420.patch 36012-diagnostic-hostname-check-420.patch

Description Janis Meybohm

2014-09-29 09:06:47 CEST

We (UMC) allow hostnames to have underscores (bug31798) presumably to be able to takeover AD domains that may contain hostnames converted from NetBIOS names that may contain underscores.

A customer reported via http://forum.univention.de/viewtopic.php?f=48&t=3492 that registering those host names in DNS may fail.

We could add a diagnostic module to check for "not RFC compliant" host names.

Comment 1 Lukas Oyen

2017-06-08 15:02:17 CEST

Created attachment 8909 [details]
36012-diagnostic-hostname-check-420.patch

Check hostnames (filter objectClass=univentionHost, attribute cn) for RFC 1123 [1] compliance. If any non-compliant hostnames are found, a Warning is raised.

[1]: https://tools.ietf.org/html/rfc1123#section-2

Comment 2 Lukas Oyen

2017-06-08 15:03:35 CEST

Created attachment 8910 [details]
36012-diagnostic-hostname-check-420.patch

Update, forgot to squash.

Comment 3 Lukas Oyen

2017-08-01 16:27:16 CEST

Committed in r81609 - r81610 (advisory r81649).

Comment 4 Jürn Brodersen

2017-08-30 15:44:58 CEST

Looks good :)

What I tested:
Checked two computers with: "cn=foo-" and "cn=foo_under" -> The diagnose module warned me about them -> OK

YAML -> OK

Note:
If I understand the RFC correctly dots in hostnames and hostnames up to 255 characters would be ok, too. But that way we might not be able to add them to the dns. Because of that I would say the regex is good.

Comment 5 Lukas Oyen

2017-09-04 09:37:50 CEST

(In reply to Jürn Brodersen from comment #4)
> If I understand the RFC correctly dots in hostnames and hostnames up to 255
> characters would be ok, too. But that way we might not be able to add them
> to the dns. Because of that I would say the regex is good.

The regex is the one from `hostName` from univention.admin.syntax without the underscores.

Comment 6 Erik Damrose

2017-09-20 15:03:38 CEST

<http://errata.software-univention.de/ucs/4.2/166.html>