Opened 7 years ago

Closed 7 years ago

Last modified 4 years ago

#9367 closed defect (wontfix)

udhcpc doesn't automatically release & renew the lease

Reported by: Raghu Pobbi Venkatachalapathy <raghupv30@…> Owned by: developers
Priority: normal Milestone: Barrier Breaker 14.07
Component: packages Version: Trunk
Keywords: Cc:



I am using the openwrt trunk (r26806) on a Atheros based device TPlink WR1043ND.
I have configured this router to act as a bridge and therefore there isonly udhcpc client running and NO dhcpd server.

Below is my test scenario:

  1. Connect the openwrt device to Network A, and check to see the unit get a new lease and has a valid valid ipaddress
  2. Unplug the wan cable from openwrt device and Replug the device to Network B ( Different network with ipaddress in different subnet)
  3. udhcpc doesn't release or request a new lease when plugged to different network and hence the device would become unreachable.

Monitoring the dhcp traffic using tcpdump doesn't find any packets.
udhcpc is from the busybox config and have configured to DEBUG level 9 in menuconfig.
Executing udhcpc with -vvv option does indicate that the udhcpc client is never signalled to release/request a new lease upon unplugg and replug of the ethernet cable to different network.

However if i can forcefully release and request a new lease by sending SIGUSR1 to udhcpc OR by restarting udhcpc.
The expected behavior would be that a new lease has to be acquired automatically

Attachments (1)

udhcpcdebug.log (7.7 KB) - added by Raghu Pobbi Venkatachalapathy <raghupv30@…> 7 years ago.

Download all attachments as: .zip

Change History (3)

Changed 7 years ago by Raghu Pobbi Venkatachalapathy <raghupv30@…>

comment:1 Changed 7 years ago by jow

  • Resolution set to wontfix
  • Status changed from new to closed

udhcpc has no concept of plugged or non plugged cables, especially on switches the vlan interface may be always up. Look into some external solutions like ifplugd or ping tests or lower your lease time.

comment:2 Changed 4 years ago by jow

  • Milestone changed from Attitude Adjustment 12.09 to Barrier Breaker 14.07

Milestone Attitude Adjustment 12.09 deleted

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