Bug 690684

Summary:	DHCP Server PAcket Loss issue
Product:	Red Hat Enterprise Linux 5	Reporter:	Athar Hussain <ather.hussain>
Component:	dhcp	Assignee:	Jiri Popelka <jpopelka>
Status:	CLOSED NOTABUG	QA Contact:	Release Test Team <release-test-team>
Severity:	urgent	Docs Contact:
Priority:	unspecified
Version:	5.2
Target Milestone:	rc
Target Release:	5.2
Hardware:	i386
OS:	Linux
Whiteboard:
Fixed In Version:		Doc Type:	Bug Fix
Doc Text:		Story Points:	---
Clone Of:		Environment:
Last Closed:	2012-05-03 09:42:09 UTC	Type:	---
Regression:	---	Mount Type:	---
Documentation:	---	CRM:
Verified Versions:		Category:	---
oVirt Team:	---	RHEL 7.3 requirements from Atomic Host:
Cloudforms Team:	---	Target Upstream Version:

Description Athar Hussain 2011-03-25 03:22:24 UTC

Description of problem:
The issue is that DHCP server only handling 20-25% request, rest of the request drop in system somewhere. We have verified TCP Dump on system OS level, Every request is coming on the system from DHCP relay agent but the system is not able to pass these request to DHCP daemon.

Version-Release number of selected component (if applicable):
DHCP 3.0.5-23

How reproducible:
Using DHCP stress test software, Which is actually emulated client.

Steps to Reproduce:
1.run the dhcp stress software from the another system
2. tcpdump on DHCP Server
3. Analyze the capture data with the packet capture software wireshark and found that only 20% DHCP request goes to the DHCP server and it acknowledge 50% request only.
  
Actual results:
Should be 100%. Why the packet is discarding ?

Expected results:
Expected result should be 100%. Every request coming on the system should go to DHCP daemon and DHCP server Should acknowledge every request.

Additional info:
Please find the attached tcpdump file for analyzing.
We are using HP DL 580G5 with 4xQuadCore processor and 12GB RAM.
We are configuring DHCP Server for Huge ISP which have already more 1 million customer in our country. Their requirement is 300 DHCP request/sec.
Please identify the issue and revert.

Comment 1 Jiri Popelka 2011-03-25 10:06:10 UTC

(In reply to comment #0)
> The issue is that DHCP server only handling 20-25% request, rest of the request
> drop in system somewhere. We have verified TCP Dump on system OS level, Every
> request is coming on the system from DHCP relay agent but the system is not
> able to pass these request to DHCP daemon.
> <snip>
> 3. Analyze the capture data with the packet capture software wireshark and
> found that only 20% DHCP request goes to the DHCP server and it acknowledge 50%
> request only.
> <snip>
> Every request coming on the system should go to
> DHCP daemon and DHCP server Should acknowledge every request.

I'm not sure I understand where the packets are dropped.
From the description it seems to me that they are dropped somewhere between the
DHCP relay agent and DHCP server.
Or do you think that it's the DHCP server who discards them ?
Which types of messages are dropped ? Only DHCPREQUESTs or also other types ?

There can be a problem with your test software.
DHCP server drops a message if it contains some inappropriate values or if it doesn't contain some required value.

> Please find the attached tcpdump file for analyzing.
There's no file attached.

Comment 2 Jiri Popelka 2012-05-03 09:42:09 UTC

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