Bug 1527806

Summary:	Updating PXE loader causes DHCP conflicts
Product:	Red Hat Satellite	Reporter:	Lukas Zapletal <lzap>
Component:	DHCP & DNS	Assignee:	Lukas Zapletal <lzap>
Status:	CLOSED ERRATA	QA Contact:
Severity:	medium	Docs Contact:
Priority:	unspecified
Version:	6.3.0	CC:	bbuckingham, ddolguik, ehelms, mhulan
Target Milestone:	Unspecified	Keywords:	Triaged
Target Release:	Unused
Hardware:	Unspecified
OS:	Unspecified
URL:	http://projects.theforeman.org/issues/21120
Whiteboard:
Fixed In Version:	foreman-1.15.6.26-1	Doc Type:	If docs needed, set a value
Doc Text:		Story Points:	---
Clone Of:		Environment:
Last Closed:	2018-02-21 16:54:37 UTC	Type:	Bug
Regression:	---	Mount Type:	---
Documentation:	---	CRM:
Verified Versions:		Category:	---
oVirt Team:	---	RHEL 7.3 requirements from Atomic Host:
Cloudforms Team:	---	Target Upstream Version:
Embargoed:

Description Lukas Zapletal 2017-12-20 07:44:03 UTC

Whenever we chage the bootloader from Grub2 UEFI to PXELinux BIOS, or vice versa, the foreman smart proxy start creating duplicate dhcp entries for this host.

how to repoduce:

1. create host with PXELinux BIOS bootloader
2. modify host to to use Grub2 UEFI
2. press submit (you will get a modal saying there already is a dhcp enty, and if you like to overwrite it)
3. acknowledge the modal and press the "overwrite" botton
4. now the "submit" button of the host is named "overwrite" -> press it
5. you will get a error message, complaining about a HTTP 409 from the dhcp smart proxy

if you check the leases file of the dhcp server, you will now have at least 2 entries for the same host. i have already see up to 33 entries for the same host within a file.

it also seems that the deleting a host will not always remove a entry from the dhcp leases file, but i have to admit that i am not 100% sure if the host will directly disappear from the leases file after it has been deleted.

to "fix" the issue, you have to:
- delete the host
- stop dhcpd
- remove broken entries from leases file
- start dhcpd
- recreate the host

Comment 4 Satellite Program 2018-02-21 16:54:37 UTC

Since the problem described in this bug report should be resolved in a recent advisory, it has been closed with a resolution of ERRATA.
> > 
> > For information on the advisory, and where to find the updated files, follow the link below.
> > 
> > If the solution does not work for you, open a new bug report.
> > 
> > https://access.redhat.com/errata/RHSA-2018:0336