A recent change to the vishvananda/netlink package exposes
NLM_F_DUMP_INTR in some netlink responses as an EINTR (with
no data).
Retry the requests when that happens, up to five times, before
returning the error. The limit of five is arbitrary, on most
systems a single retry will be rare but, there's no guarantee
that a retry will succeed. So, on a very busy or misbehaving
system the error may still be returned. In most cases, this
will lead to failure of the operation being attempted (which
may lead to daemon startup failure, network initialisation
failure etc).
Signed-off-by: Rob Murray <rob.murray@docker.com>
Calculate the IPv6 addreesses needed on a bridge, then reconcile them
with the addresses on an existing bridge by deleting then adding as
required.
(Previously, required addresses were added one-by-one, then unwanted
addresses were removed. This meant the daemon failed to start if, for
example, an existing bridge had address '2000:db8::/64' and the config
was changed to '2000:db8::/80'.)
IPv6 addresses are now calculated and applied in one go, so there's no
need for setupVerifyAndReconcile() to check the set of IPv6 addresses on
the bridge. And, it was guarded by !config.InhibitIPv4, which can't have
been right. So, removed its IPv6 parts, and added IPv4 to its name.
Link local addresses, the example given in the original ticket, are now
released when containers are stopped. Not releasing them meant that
when using an LL subnet on the default bridge, no container could be
started after a container was stopped (because the calculated address
could not be re-allocated). In non-default bridge networks using an
LL subnet, addresses leaked.
Linux always uses the standard 'fe80::/64' LL network. So, if a bridge
is configured with an LL subnet prefix that overlaps with it, a config
error is reported. Non-overlapping LL subnet prefixes are allowed.
Signed-off-by: Rob Murray <rob.murray@docker.com>
This makes it easier to spot if code is only used on Linux. Note that "all of"
the bridge driver is Linux-only.
Signed-off-by: Sebastiaan van Stijn <github@gone.nl>
