If the kernel receives a negative nsid it will automatically assign
the next available nsid. In this case alloc_netid() will set min and
max to 0 for ird_alloc(). And when max == 0 idr_alloc() will interpret
this as the maximum range, i.e. specific to nsids it will try to find
an id in the range [0,INT_MAX). This is intentionally supported in the
kernel for nsids.
Commit acbe9118ce ("ip netns: use strtol() instead of atoi()")
regressed ip netns in that respect although previously the use-case
was either accidentally supported or opaquely supported such that it
triggered the original commit. From what I can gather it went as
follows before: atoi() was called with a string indicating a negative
value which caused it to return -1 which was passed to the
kernel. Let's make it less opaque by introducing the keyword "auto":
ip netns set <netns-name> auto
will cause nsid to be set to -1 and the kernel will select an available
nsid.
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
Signed-off-by: Stephen Hemminger <stephen@networkplumber.org>
Use brackets to show that 'ip netns' defaults to action 'list', drop
superfluous curly braces around 'set' action keyword.
Signed-off-by: Phil Sutter <phil@nwl.cc>
Two commands are added:
- ip netns list-id
- ip monitor nsid
A cache is also added to remember the association between the iproute2 netns
name (from /var/run/netns/) and the nsid.
To avoid interfering with the rth socket, a new rtnl socket (rtnsh) is used to
get nsid (we may send rtnl request during listing on rth).
Example:
$ ip netns list-id
nsid 0 (iproute2 netns name: foo)
$ ip monitor nsid
Deleted nsid 0 (iproute2 netns name: foo)
nsid 16 (iproute2 netns name: bar)
Signed-off-by: Nicolas Dichtel <nicolas.dichtel@6wind.com>
The kernel now provides ids for peer netns. This patch implements a new command
'set' to assign an id.
When netns are listed, if an id is assigned, it is now displayed.
Example:
$ ip netns add foo
$ ip netns set foo 1
$ ip netns
foo (id: 1)
init_net
Signed-off-by: Nicolas Dichtel <nicolas.dichtel@6wind.com>
This change allows to exec some cmd on each
named netns (except default) by specifying '-all' option:
# ip -all netns exec ip link
Each command executes synchronously.
Exit status is not considered, so there might be a case
that some CMD can fail on some netns but success on the other.
EXAMPLES:
1) Show link info on all netns:
$ ip -all netns exec ip link
netns: test_net
1: lo: <LOOPBACK> mtu 65536 qdisc noop state DOWN mode DEFAULT group default
link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
4: tap0: <NO-CARRIER,BROADCAST,MULTICAST,UP> mtu 1500 qdisc pfifo_fast state DOWN mode DEFAULT group default qlen 500
link/ether 1a:19:6f:25:eb:85 brd ff:ff:ff:ff:ff:ff
netns: home0
1: lo: <LOOPBACK> mtu 65536 qdisc noop state DOWN mode DEFAULT group default
link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
4: tap0: <NO-CARRIER,BROADCAST,MULTICAST,UP> mtu 1500 qdisc pfifo_fast state DOWN mode DEFAULT group default qlen 500
link/ether ea:1a:59:40:d3:29 brd ff:ff:ff:ff:ff:ff
netns: lan0
1: lo: <LOOPBACK> mtu 65536 qdisc noop state DOWN mode DEFAULT group default
link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
4: tap0: <NO-CARRIER,BROADCAST,MULTICAST,UP> mtu 1500 qdisc pfifo_fast state DOWN mode DEFAULT group default qlen 500
link/ether ce:49:d5:46:81:ea brd ff:ff:ff:ff:ff:ff
2) Set UP tap0 device for the all netns:
$ ip -all netns exec ip link set dev tap0 up
netns: test_net
netns: home0
netns: lan0
Signed-off-by: Vadim Kochan <vadim4j@gmail.com>
As 'ip' util will share the same netns from the caller
process then we can just look at /proc/self/.. to show
the netns of the current process by:
ip netns id
Signed-off-by: Vadim Kochan <vadim4j@gmail.com>
Enclosed patch fixes inappropriate uses of the .SS macro. Fuller explanation
in the change comment.
There are other problems in these pages that block lifting to
XML-DocBook, most notably in the command synopses. They will take
some creativity to fix. I'm working on it
>From 75745adba4b45b87577b61a2daa886dd444f44da Mon Sep 17 00:00:00 2001
From: "Eric S. Raymond" <esr@thyrsus.com>
Date: Fri, 21 Jun 2013 15:27:38 -0400
Subject: [PATCH] Abolish presentation-level misuse of the .SS macro.
This change fixes most (but not all) fatal errors in attempts to lift
the iproute2 manual pages to XML-DocBook. Where .SS is still used it
is a real subsection header, not just a way to outdent and bold text.
Presentation-level instances are turned into .TP calls and tables.
Rephrasing for clarity.
Note that in ip-rule.8 I rephrased a sentence to "The RPDB is scanned
in order of decreasing priority." The original version talked about
*in*creasing priority, but from the context that didn't make sense.
Signed-off-by: Kees van Reeuwijk <reeuwijk@few.vu.nl>
Add command that go between network namespace names and process
identifiers. The code builds and runs agains older kernels but
only works on Linux 3.8+ kernels where I have fixed stat to work
properly.
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Document ip netns monitor.
Add a few senteces describing each command. The manpage was looking
very scrawny.
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
