Bug #147

Router doesn't get DHCP address unless it's rebooted

Added by Srikanth Sundaresan on May 15, 2011. Updated on Sep 20, 2011.
New High Dave Täht

Description

If the router boots up without a WAN connection, it doesn’t get a dhcp address once connected. Needs a reboot.
udhcpc is up, but not working properly.

History

Updated by Srikanth Sundaresan on May 15, 2011.
Complex. Once the main DHCP server (that gives out the lease) has a cache, the wan interface is able to get an address.

Behavior is udhcpc polls continuously for a DHCP address when the link is down. When the link goes up, theory is unless the main router has an ARP cache for the secondary router, it fails to provide an address.

Updated by Dave Täht on May 15, 2011.
There are patches that landed in main openwrt and my mailbox over the last few days that revise link-state negotiation somewhat. They may help. They may hurt. As extensive QA has already been performed down to the kernel level, and fiddling with such a complex, critical system at this late date introduces other risks, I would prefer to not deal with this one, as it seems hard to reproduce.

unless this proves a serious problem (please, more people duplicate) I would prefer to remain frozen so that future routers can be updated via opkg rather than a complete new sysupgrade.

Updated by Dave Täht on May 22, 2011.
I will look further into this upon the next release of cerowrt and/or iscwrt.
Updated by Dave Täht on May 22, 2011.
Updated by Dave Täht on Jul 31, 2011.
Updated by Jim Gettys on Sep 20, 2011.

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