When syncing data from neutron server, metering-agent may receive
information about routers that are not hosted by the l3-agent on the
same host, because the server didn't filter them out. This could lead to
the following problems:
* metering-agent tries to setup iptables rules for a router that is not
on the host
* metering-agent tries to get get traffic counters for a router that
was once on the host but is already removed
* metering-agent not sets up iptables rules for a router that is
removed then added back to the host, because nothing about the
router is changed from metering-agent's perspective
This commit fixes the aforementioned problems by making metering-agent
only receive information about routers that are on the same host, and
update metering-agent's knowledge about which routers it should care.
However, there could still be problem if one removes then adds a router
back to the same l3-agent, or just sets the router's admin_state_up
property to False then True in a short time(shorter than the interval
between two syncs). Because the metering-agent sees nothing changed
while during the same time the router's namespace is removed and added
back on the host. Thus metering-agent will fail to get such router's
traffic counters. This commit also make iptables-driver to forget such
routers and leave the metering-agent to reconfigure them later.
Closes-Bug: #1580548
Change-Id: Ia6ae82c676582b06710d6f96b9938c215258182d
Signed-off-by: Hunt Xu <mhuntxu@gmail.com>
7962dd49ef