Bug 3389

Summary:	No notification of duplicate IP
Product:	[Retired] Red Hat Linux	Reporter:	jmuller
Component:	kernel	Assignee:	David Lawrence <dkl>
Status:	CLOSED WONTFIX	QA Contact:
Severity:	medium	Docs Contact:
Priority:	medium
Version:	6.0
Target Milestone:	---
Target Release:	---
Hardware:	All
OS:	Linux
Whiteboard:
Fixed In Version:		Doc Type:	Bug Fix
Doc Text:		Story Points:	---
Clone Of:		Environment:
Last Closed:	1999-07-29 20:56:40 UTC	Type:	---
Regression:	---	Mount Type:	---
Documentation:	---	CRM:
Verified Versions:		Category:	---
oVirt Team:	---	RHEL 7.3 requirements from Atomic Host:
Cloudforms Team:	---	Target Upstream Version:
Embargoed:

Description jmuller 1999-06-10 15:21:33 UTC

Yesterday someone setup a Red Hat 6.0 box on our network
and unfortunately assigned the same IP as our Red Hat 5.2
server.  Needless to say both interfaces completely shut
down, without out logging any errors or any notification.
After much frustration we finally figured out what
happened.  If Windows 95 can tell you there is a duplicate
IP out there I think Linux should as well.

Comment 1 Jeff Johnson 1999-06-10 15:39:59 UTC

I'm changing the component to kernel because that's where
unices usually detect this problem.

Comment 2 Jeff Johnson 1999-06-10 15:42:59 UTC

You might also consider running arpwatch on a 3rd machine and
monitoring the output. Arpwatch mails a message to root
every time a new IP/MAC pair is detected. That might be
sufficient for you to detect duplicated IP addr's but would
require a 3rd machine and some sys admin work ...

Comment 3 Alan Cox 1999-06-12 13:07:59 UTC

Be very careful how you handle this. The Windows 95 "feature" is used
regularly as a denial of service attack on windows networks by
slamming the lan with faked addresses. It is possible to put it in the
kernel but non trivial to do it right.

If we need a patch for it I can knock one up

Comment 4 Michael K. Johnson 1999-07-29 20:56:59 UTC

Resolved as "WONTFIX" because we aren't likely to fix this in
the near future; there are no plans to fix it for the next
release or next beta release or anything like that.