Bug 685048

Summary: No IP connectivity with DHCP when Link was down on boot
Product: Red Hat Enterprise Linux 5 Reporter: Masahiro Matsuya <mmatsuya>
Component: dhcpAssignee: Jiri Popelka <jpopelka>
Status: CLOSED ERRATA QA Contact: Release Test Team <release-test-team>
Severity: medium Docs Contact:
Priority: medium    
Version: 5.7CC: atodorov, jstodola, ovasik, tcapek
Target Milestone: rc   
Target Release: ---   
Hardware: All   
OS: Linux   
Whiteboard:
Fixed In Version: dhcp-3.0.5-27.el5 Doc Type: Bug Fix
Doc Text:
Previously, when the system had been rebooted while the network switch had been down, after the network connection was recovered, the network interface configuration was not configured with DHCP, even if the dhclient utility was running in persistent mode. With this update, the dhclient-script file has been amended to refresh the ARP (Address Resolution Protocol) table and the routing table instead of bringing the interface down, which fixes the bug.
Story Points: ---
Clone Of:
: 694799 (view as bug list) Environment:
Last Closed: 2011-07-21 10:59:09 UTC Type: ---
Regression: --- Mount Type: ---
Documentation: --- CRM:
Verified Versions: Category: ---
oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
Cloudforms Team: --- Target Upstream Version:
Bug Depends On:    
Bug Blocks: 694799    
Attachments:
Description Flags
backported patch none

Description Masahiro Matsuya 2011-03-15 07:03:36 UTC
Created attachment 484374 [details]
backported patch

Description of problem:
A customer rebooted their system while the network switch is down.
/etc/sysconfig/network-scripts/ifcfg-eth0 on the system has
PERSISTENT_DHCLIENT=yes, but dhclient did not start. Another bugzilla BZ685038 was opened for initscript package. But, it is not enough.

After the following are outputed and network connection recovers, the network interface configuration like ip address is not configured with dhcp yet, though dhcpclient is running.

Feb 19 16:47:24 dhcp209-249 dhclient: No working leases in persistent database - sleeping.
Feb 19 16:47:24 dhcp209-249 dhclient: receive_packet failed on eth1: Network is down

It is because dhclient script makes the interface down, not just refleshing arp table and routing table.
I will attach the backported patch from upstream on this bugzilla.

Version-Release number of selected component (if applicable):
RHEL5.6
dhcp-3.0.5-23.el5_5.2

How reproducible:
Always

Steps to Reproduce:
1. configure PERSISTENT_DHCLIENT=yes for eth0
2. ifdown eth0
3. remove the ethernet cable from eth0
4. ifup eth0, and confirm if dhclient is running.
5. wait for a while and check the following message in /var/log/messages

Feb 19 16:47:24 dhcp209-249 dhclient: No working leases in persistent database - sleeping.
Feb 19 16:47:24 dhcp209-249 dhclient: receive_packet failed on eth1: Network is down

6. insert the ethernet cable again, and check if this problem occurs with ip or ifconfig command.

Actual results:
The network interface configuration is not configured with dhcp, even though dhclient is running.

Expected results:
The network interface configuration is configured with dhcp, after the network connection recovers.

Additional info:

Comment 1 Jiri Popelka 2011-03-15 15:10:54 UTC
Thank you very much for your effort with investigating the problem and back-porting the patch.

Yes, the upstream (Fedora) bug for this problem is bug #574568.
And as you can see in bug #574568, comment #2 I wasn't able to reproduce the problem on my hardware (it's probably HW specific problem).

So, can you confirm that the attached patch fixes the problem reported by customer ?

Comment 2 Masahiro Matsuya 2011-03-16 02:16:12 UTC
Yes, I confirmed that it fixed the problem in my test machine. 
I created the test packages for the customer. If they can confirm the fix, I will update it on this bugzilla.

Comment 7 Tomas Capek 2011-05-31 08:18:48 UTC
    Technical note added. If any revisions are required, please edit the "Technical Notes" field
    accordingly. All revisions will be proofread by the Engineering Content Services team.
    
    New Contents:
Previously, when the system had been rebooted while the network switch had been down, after the network connection was recovered, the network interface configuration was not configured with DHCP, even if the dhclient utility was running in persistent mode. With this update, the dhclient-script file has been amended to refresh the ARP (Address Resolution Protocol) table and the routing table instead of bringing the interface down, which fixes the bug.

Comment 8 Jan Stodola 2011-06-02 13:49:05 UTC
Tested with dhclient-3.0.5-29.el5 using steps from comment 0.

After plugging the cable, dhclient requested an IP address, which was successfully assigned to the network interface and networking started to work.

Moving to VERIFIED.

Comment 9 errata-xmlrpc 2011-07-21 10:59:09 UTC
An advisory has been issued which should help the problem
described in this bug report. This report is therefore being
closed with a resolution of ERRATA. For more information
on therefore solution and/or where to find the updated files,
please follow the link below. You may reopen this bug report
if the solution does not work for you.

http://rhn.redhat.com/errata/RHBA-2011-1038.html