# Revision history [back]

### Asymetric ARP & DHCP issues on GRE tenant net...

bootpc and arp requests from instances using GRE tenant networks are not making it onto the physical network, I suspect this is "all broadcast traffic". If IP is configured statically and the arp cache is set (by pinging from the other end, network controller in this case) I can communicate over the link, until the arp cache times out...

This was perviously woking. Last know to work prior to teh upgrade from Grizzly to Havana at the beginning of January. As this isn't a widely used feature I'm uncertain if it broke during upgrade or sometime just before or just after.

By fiddling with ovs port mirroring I've been able to determine where the packets disappear from my expected path (and verified that packets are visible at these point when traffic is passing). Packets get as far as patch-int in the br-tun but do not appear on the gre-<n> device:

tap                -> patch-tun        -> patch-int     ->   gre-<N>         -> eth0
(has packets)        (has packets)      (still there)   !!   (no packets)       (no packets)
\_________________________________/     \________________________________/      (GRE wrapped)
br-int                               br-tun                        IP of tunnel endpoint


How can I fix this? The nodes are in production and most instances use VLAN based provider networks which work fine, so reboot and try again isn't really an option, bu tif there is a way to reset all the virtual networking state I could take a few second network blip if I had to...setup is Ubuntu 12.04 w/ Havana cloud archive packages

### Asymetric ARP & DHCP issues on GRE tenant net...

bootpc and arp requests from instances using GRE tenant networks are not making it onto the physical network, I suspect this is "all broadcast traffic". If IP is configured statically and the arp cache is set (by pinging from the other end, network controller in this case) I can communicate over the link, until the arp cache times out...out...note that manually setting the arp cache on the instance with arp -s does not work, so probably more than just broadcast flows getting screwed up.

This was perviously woking. Last know to work prior to teh upgrade from Grizzly to Havana at the beginning of January. As this isn't a widely used feature I'm uncertain if it broke during upgrade or sometime just before or just after.

By fiddling with ovs port mirroring I've been able to determine where the packets disappear from my expected path (and verified that packets are visible at these point when traffic is passing). Packets get as far as patch-int in the br-tun but do not appear on the gre-<n> device:

tap                -> patch-tun        -> patch-int     ->   gre-<N>         -> eth0
(has packets)        (has packets)      (still there)   !!   (no packets)       (no packets)
\_________________________________/     \________________________________/      (GRE wrapped)
br-int                               br-tun                        IP of tunnel endpoint


How can I fix this? The nodes are in production and most instances use VLAN based provider networks which work fine, so reboot and try again isn't really an option, bu tif there is a way to reset all the virtual networking state I could take a few second network blip if I had to...setup is Ubuntu 12.04 w/ Havana cloud archive packages