mirror of
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
synced 2026-09-17 09:41:09 +02:00
William Dauchy
5fdcce211b
With ipip, it is possible to create an extra interface explicitly
attached to a given physical interface:
# ip link show tunl0
4: tunl0@NONE: <NOARP> mtu 1480 qdisc noop state DOWN mode DEFAULT group default qlen 1000
link/ipip 0.0.0.0 brd 0.0.0.0
# ip link add tunl1 type ipip dev eth0
# ip link show tunl1
6: tunl1@eth0: <NOARP> mtu 1480 qdisc noop state DOWN mode DEFAULT group default qlen 1000
link/ipip 0.0.0.0 brd 0.0.0.0
But it is not possible with ip6tnl:
# ip link show ip6tnl0
5: ip6tnl0@NONE: <NOARP> mtu 1452 qdisc noop state DOWN mode DEFAULT group default qlen 1000
link/tunnel6 :: brd ::
# ip link add ip6tnl1 type ip6tnl dev eth0
RTNETLINK answers: File exists
This patch aims to make it possible by adding link comparaison in both
tunnel locate and lookup functions; we also modify mtu calculation when
attached to an interface with a lower mtu.
This permits to make use of x-netns communication by moving the newly
created tunnel in a given netns.
Signed-off-by: William Dauchy <w.dauchy@criteo.com>
Reviewed-by: Nicolas Dichtel <nicolas.dichtel@6wind.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Linux kernel
============
There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.
In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``. The formatted documentation can also be read online at:
https://www.kernel.org/doc/html/latest/
There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.
Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.