[Cerowrt-devel] DHCPv4 lease file empty, DHCPv6 lease shows "expired"
simon at thekelleys.org.uk
Tue May 6 14:12:50 EDT 2014
On 04/05/14 22:00, Chuck Anderson wrote:
> b. Modify dnsmasq and odhcpd to measure elapsed time rather than
> storing the current wallclock time-of-day for the start of each
> lease. Maybe using the Linux system uptime seconds-since-boot
> would work.
Dnsmasq can do this already. Build with -DHAVE_BROKEN_RTC
> Unfortunately, this would be problematic for
> maintaining leases when the system is rebooted. Does Cero/OpenWrt
> even maintain leases over reboots? The RFCs say this is mandatory,
> but I wonder given that the lease files are stored under /tmp. Is
> /tmp maintained over reboots?
I don't know if CeroWRT keeps the leases in non-volatile storage, but if
it does, then dnsmasq with HAVE_BROKEN_RTC keeps lease-time-remaining
rather then time-lease-expires, so the effect of a reboot is simply to
extend DHCP leases for the duration of the downtime.
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