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1.37. dhcp

1.37.1. RHBA-2010:0042: bug fix update

Note

This update has already been released (prior to the GA of this release) as errata RHBA-2010:0042
A dhcp update that fixes one memory leak is now available.
The Dynamic Host Configuration Protocol (DHCP) is a protocol that allows individual devices on an IP network to get their own network configuration information, including an IP address, a subnet mask, and a broadcast address. The dhcp package provides a relay agent and ISC DHCP service required to enable and administer DHCP on a network.
This update applies the following updates:
* a memory leak in the load_balance_mine() function caused dhcpd, the dhcp server, to leak approximately 20-30 octets per DHCPDISCOVER packet when the server was configured for failover and failover was in a normal state. This particular leak has been closed with this update. (BZ#552211)
Note: depending on the specific DHCP setup on a given system, other memory leaks may still present. Please file a separate bug if DHCP appears to leak memory after applying this update.
All dhcp users should to apply this update which closes this memory leak.

1.37.2. RHBA-2010:0223: bug fix update

A dhcp update that fixes bugs is now available.
DHCP (Dynamic Host Configuration Protocol) is a protocol which allows individual devices on an IP network to get their own network configuration information (IP address, subnetmask, broadcast address, etc.) from a DHCP server.
These updated packages address the following issues:
* When a system running a dhclient received a very short lease (e.g a few seconds), it would constantly have to request a renewal of its lease. The system would spend so much time running the dhclient-script every time it made a request that it would become almost unresponsive. A patch has been added to the code, setting the minimum lease time to 60 seconds. By preventing very short lease times, the server no longer becomes unresponsive from an overload of renewal requests. (BZ#498658)
* When the $localClockFudge variable was empty, the /sbin/dhclient-script added an empty line to the /etc/ntp.conf file when renewing the DHCP lease. This caused the diff command to fail when there was no meaningful difference between the old and new files, thus restarting the NTP daemon unnecessarily. This put useless noise in the log files that get picked up by logwatch. This update provides a slight code change that configures the NTP daemon differently. The /etc/ntp.conf file now only runs if there is a useful value in the $localClockFudge variable. (BZ#532136)
* A memory leak in the load_balance_mine() function caused 20-30 octets per DHCPDISCOVER packet to be leaked when failover was in use and was in its normal state. This caused the performance of the server to be significantly diminished. This update fixes the memory leak in the load_balance_mine() function, allowing the server to perform correctly. (BZ#534117)
Note: depending on the specific DHCP setup on a given system, other memory leaks may still present. Please file a separate bug if DHCP appears to leak memory after applying this update.
* A syntax error was discovered in the code of the initscript for the dhcrelay. In the process of restarting, the service would shutdown, but the initscript would fail when attempting to start the service again. A patch has been added, correcting the syntax error in the code. This correction now allows the service to restart correctly. (BZ#555672)
Users are advised to upgrade to these updated dhcp packages which resolve these issues.