Re: [OpenWrt-Devel] Retaining WAN IP addresses across reboots
All of the platforms I have use a CMOS NVRAM with RTC built-in. On 4/12/11 5:02 PM, Nuno Gonçalves wrote: Please also note that the real time clock is important for knowing if the DHCP lease is still valid. Since most routers don't have a hardware RTC, there is no way to know it the DHCP lease is still valid before you get WAN connectivity to update the time with NTP. Nuno On Tue, Apr 12, 2011 at 05:15, Stefan Monnier monn...@iro.umontreal.ca wrote: I note that the file /tmp/state/network contains the interface, ip address, and expiration time of the WAN DHCP lease... I'm wondering what's involved in writing that information into somewhere persistent where it can be reused on reboot? You may want to start by replacing the /var symlink to /tmp by a real directory. OpenWRT should be using the /var/state/network filename, so after performing the above change, the file will be preserved across reboots. If not, report it as a bug. I'm not sure if OpenWRT will later start udhcpd in such a way as to take advantage of this pre-existing file, but that's a second step. Stefan ___ openwrt-devel mailing list openwrt-devel@lists.openwrt.org https://lists.openwrt.org/mailman/listinfo/openwrt-devel
Re: [OpenWrt-Devel] Retaining WAN IP addresses across reboots
On 4/13/11 1:16 PM, edgar.sol...@web.de wrote: On 13.04.2011 19:18, Philip Prindeville wrote: All of the platforms I have use a CMOS NVRAM with RTC built-in. do they have names? ;) ..ede Alix, net5501, Geos... and a couple of others that haven't yet been publicly announced. ___ openwrt-devel mailing list openwrt-devel@lists.openwrt.org https://lists.openwrt.org/mailman/listinfo/openwrt-devel
Re: [OpenWrt-Devel] Retaining WAN IP addresses across reboots
I was thinking about this some more... if we simply took the leased IP address and stuffed it up into: config 'wan' option ipaddr x.x.x.x in network, the /lib/network/config.sh script would then try to request that address the next time the box rebooted. If the address was in use, then we'd be NAK'd the address by the DHCP server, and we'd retry with no address, right? So it wouldn't really matter if the lease had expired or not, in the end... because the server knows if it has in any case. -Philip On 4/12/11 5:02 PM, Nuno Gonçalves wrote: Please also note that the real time clock is important for knowing if the DHCP lease is still valid. Since most routers don't have a hardware RTC, there is no way to know it the DHCP lease is still valid before you get WAN connectivity to update the time with NTP. Nuno On Tue, Apr 12, 2011 at 05:15, Stefan Monnier monn...@iro.umontreal.ca wrote: I note that the file /tmp/state/network contains the interface, ip address, and expiration time of the WAN DHCP lease... I'm wondering what's involved in writing that information into somewhere persistent where it can be reused on reboot? You may want to start by replacing the /var symlink to /tmp by a real directory. OpenWRT should be using the /var/state/network filename, so after performing the above change, the file will be preserved across reboots. If not, report it as a bug. I'm not sure if OpenWRT will later start udhcpd in such a way as to take advantage of this pre-existing file, but that's a second step. Stefan ___ openwrt-devel mailing list openwrt-devel@lists.openwrt.org https://lists.openwrt.org/mailman/listinfo/openwrt-devel
Re: [OpenWrt-Devel] Retaining WAN IP addresses across reboots
Please also note that the real time clock is important for knowing if the DHCP lease is still valid. Since most routers don't have a hardware RTC, there is no way to know it the DHCP lease is still valid before you get WAN connectivity to update the time with NTP. Nuno On Tue, Apr 12, 2011 at 05:15, Stefan Monnier monn...@iro.umontreal.ca wrote: I note that the file /tmp/state/network contains the interface, ip address, and expiration time of the WAN DHCP lease... I'm wondering what's involved in writing that information into somewhere persistent where it can be reused on reboot? You may want to start by replacing the /var symlink to /tmp by a real directory. OpenWRT should be using the /var/state/network filename, so after performing the above change, the file will be preserved across reboots. If not, report it as a bug. I'm not sure if OpenWRT will later start udhcpd in such a way as to take advantage of this pre-existing file, but that's a second step. Stefan ___ openwrt-devel mailing list openwrt-devel@lists.openwrt.org https://lists.openwrt.org/mailman/listinfo/openwrt-devel ___ openwrt-devel mailing list openwrt-devel@lists.openwrt.org https://lists.openwrt.org/mailman/listinfo/openwrt-devel
Re: [OpenWrt-Devel] Retaining WAN IP addresses across reboots
I note that the file /tmp/state/network contains the interface, ip address, and expiration time of the WAN DHCP lease... I'm wondering what's involved in writing that information into somewhere persistent where it can be reused on reboot? You may want to start by replacing the /var symlink to /tmp by a real directory. OpenWRT should be using the /var/state/network filename, so after performing the above change, the file will be preserved across reboots. If not, report it as a bug. I'm not sure if OpenWRT will later start udhcpd in such a way as to take advantage of this pre-existing file, but that's a second step. Stefan ___ openwrt-devel mailing list openwrt-devel@lists.openwrt.org https://lists.openwrt.org/mailman/listinfo/openwrt-devel
[OpenWrt-Devel] Retaining WAN IP addresses across reboots
I note that the file /tmp/state/network contains the interface, ip address, and expiration time of the WAN DHCP lease... I'm wondering what's involved in writing that information into somewhere persistent where it can be reused on reboot? If, for instance, a previous boot acquired a lease for x.x.x.x and it hasn't yet expired before we reboot... can we just reprime the lease request with the same IP address? Udhcpc allows this to be done with the -r x.x.x.x option. Of course, that starts the entire lease negotiation process from the DISCOVERY process, as opposed to using the entire lease state (including transaction ID) to do a simple lease renewal via a REQUEST message instead. Ideally, we'd simply reuse the original lease if it hadn't expired, but currently udhcpc doesn't allow this. -Philip ___ openwrt-devel mailing list openwrt-devel@lists.openwrt.org https://lists.openwrt.org/mailman/listinfo/openwrt-devel
