[deliverable/linux.git] / Documentation / networking / vrf.txt

Virtual Routing and Forwarding (VRF)
====================================
The VRF device combined with ip rules provides the ability to create virtual
routing and forwarding domains (aka VRFs, VRF-lite to be specific) in the
Linux network stack. One use case is the multi-tenancy problem where each
tenant has their own unique routing tables and in the very least need
different default gateways.

Processes can be "VRF aware" by binding a socket to the VRF device. Packets
through the socket then use the routing table associated with the VRF
device. An important feature of the VRF device implementation is that it
impacts only Layer 3 and above so L2 tools (e.g., LLDP) are not affected
(ie., they do not need to be run in each VRF). The design also allows
the use of higher priority ip rules (Policy Based Routing, PBR) to take
precedence over the VRF device rules directing specific traffic as desired.

In addition, VRF devices allow VRFs to be nested within namespaces. For
example network namespaces provide separation of network interfaces at the
device layer, VLANs on the interfaces within a namespace provide L2 separation
and then VRF devices provide L3 separation.

Design
------
A VRF device is created with an associated route table. Network interfaces
are then enslaved to a VRF device:

         +-----------------------------+
         |           vrf-blue          |  ===> route table 10
         +-----------------------------+
            |        |            |
         +------+ +------+     +-------------+
         | eth1 | | eth2 | ... |    bond1    |
         +------+ +------+     +-------------+
                                  |       |
                              +------+ +------+
                              | eth8 | | eth9 |
                              +------+ +------+

Packets received on an enslaved device and are switched to the VRF device
in the IPv4 and IPv6 processing stacks giving the impression that packets
flow through the VRF device. Similarly on egress routing rules are used to
send packets to the VRF device driver before getting sent out the actual
interface. This allows tcpdump on a VRF device to capture all packets into
and out of the VRF as a whole.[1] Similarly, netfilter[2] and tc rules can be
applied using the VRF device to specify rules that apply to the VRF domain
as a whole.

[1] Packets in the forwarded state do not flow through the device, so those
    packets are not seen by tcpdump. Will revisit this limitation in a
    future release.

[2] Iptables on ingress supports PREROUTING with skb->dev set to the real
    ingress device and both INPUT and PREROUTING rules with skb->dev set to
    the VRF device. For egress POSTROUTING and OUTPUT rules can be written
    using either the VRF device or real egress device.

Setup
-----
1. VRF device is created with an association to a FIB table.
   e.g, ip link add vrf-blue type vrf table 10
        ip link set dev vrf-blue up

2. An l3mdev FIB rule directs lookups to the table associated with the device.
   A single l3mdev rule is sufficient for all VRFs. The VRF device adds the
   l3mdev rule for IPv4 and IPv6 when the first device is created with a
   default preference of 1000. Users may delete the rule if desired and add
   with a different priority or install per-VRF rules.

   Prior to the v4.8 kernel iif and oif rules are needed for each VRF device:
       ip ru add oif vrf-blue table 10
       ip ru add iif vrf-blue table 10

3. Set the default route for the table (and hence default route for the VRF).
       ip route add table 10 unreachable default

4. Enslave L3 interfaces to a VRF device.
       ip link set dev eth1 master vrf-blue

   Local and connected routes for enslaved devices are automatically moved to
   the table associated with VRF device. Any additional routes depending on
   the enslaved device are dropped and will need to be reinserted to the VRF
   FIB table following the enslavement.

   The IPv6 sysctl option keep_addr_on_down can be enabled to keep IPv6 global
   addresses as VRF enslavement changes.
       sysctl -w net.ipv6.conf.all.keep_addr_on_down=1

5. Additional VRF routes are added to associated table.
       ip route add table 10 ...


Applications
------------
Applications that are to work within a VRF need to bind their socket to the
VRF device:

    setsockopt(sd, SOL_SOCKET, SO_BINDTODEVICE, dev, strlen(dev)+1);

or to specify the output device using cmsg and IP_PKTINFO.

TCP services running in the default VRF context (ie., not bound to any VRF
device) can work across all VRF domains by enabling the tcp_l3mdev_accept
sysctl option:
    sysctl -w net.ipv4.tcp_l3mdev_accept=1

netfilter rules on the VRF device can be used to limit access to services
running in the default VRF context as well.

The default VRF does not have limited scope with respect to port bindings.
That is, if a process does a wildcard bind to a port in the default VRF it
owns the port across all VRF domains within the network namespace.

################################################################################

Using iproute2 for VRFs
=======================
iproute2 supports the vrf keyword as of v4.7. For backwards compatibility this
section lists both commands where appropriate -- with the vrf keyword and the
older form without it.

1. Create a VRF

   To instantiate a VRF device and associate it with a table:
       $ ip link add dev NAME type vrf table ID

   As of v4.8 the kernel supports the l3mdev FIB rule where a single rule
   covers all VRFs. The l3mdev rule is created for IPv4 and IPv6 on first
   device create.

2. List VRFs

   To list VRFs that have been created:
       $ ip [-d] link show type vrf
         NOTE: The -d option is needed to show the table id

   For example:
   $ ip -d link show type vrf
   11: mgmt: <NOARP,MASTER,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP mode DEFAULT group default qlen 1000
       link/ether 72:b3:ba:91:e2:24 brd ff:ff:ff:ff:ff:ff promiscuity 0
       vrf table 1 addrgenmode eui64
   12: red: <NOARP,MASTER,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP mode DEFAULT group default qlen 1000
       link/ether b6:6f:6e:f6:da:73 brd ff:ff:ff:ff:ff:ff promiscuity 0
       vrf table 10 addrgenmode eui64
   13: blue: <NOARP,MASTER,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP mode DEFAULT group default qlen 1000
       link/ether 36:62:e8:7d:bb:8c brd ff:ff:ff:ff:ff:ff promiscuity 0
       vrf table 66 addrgenmode eui64
   14: green: <NOARP,MASTER,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP mode DEFAULT group default qlen 1000
       link/ether e6:28:b8:63:70:bb brd ff:ff:ff:ff:ff:ff promiscuity 0
       vrf table 81 addrgenmode eui64


   Or in brief output:

   $ ip -br link show type vrf
   mgmt         UP             72:b3:ba:91:e2:24 <NOARP,MASTER,UP,LOWER_UP>
   red          UP             b6:6f:6e:f6:da:73 <NOARP,MASTER,UP,LOWER_UP>
   blue         UP             36:62:e8:7d:bb:8c <NOARP,MASTER,UP,LOWER_UP>
   green        UP             e6:28:b8:63:70:bb <NOARP,MASTER,UP,LOWER_UP>


3. Assign a Network Interface to a VRF

   Network interfaces are assigned to a VRF by enslaving the netdevice to a
   VRF device:
       $ ip link set dev NAME master NAME

   On enslavement connected and local routes are automatically moved to the
   table associated with the VRF device.

   For example:
   $ ip link set dev eth0 master mgmt


4. Show Devices Assigned to a VRF

   To show devices that have been assigned to a specific VRF add the master
   option to the ip command:
       $ ip link show vrf NAME
       $ ip link show master NAME

   For example:
   $ ip link show vrf red
   3: eth1: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast master red state UP mode DEFAULT group default qlen 1000
       link/ether 02:00:00:00:02:02 brd ff:ff:ff:ff:ff:ff
   4: eth2: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast master red state UP mode DEFAULT group default qlen 1000
       link/ether 02:00:00:00:02:03 brd ff:ff:ff:ff:ff:ff
   7: eth5: <BROADCAST,MULTICAST> mtu 1500 qdisc noop master red state DOWN mode DEFAULT group default qlen 1000
       link/ether 02:00:00:00:02:06 brd ff:ff:ff:ff:ff:ff


   Or using the brief output:
   $ ip -br link show vrf red
   eth1             UP             02:00:00:00:02:02 <BROADCAST,MULTICAST,UP,LOWER_UP>
   eth2             UP             02:00:00:00:02:03 <BROADCAST,MULTICAST,UP,LOWER_UP>
   eth5             DOWN           02:00:00:00:02:06 <BROADCAST,MULTICAST>


5. Show Neighbor Entries for a VRF

   To list neighbor entries associated with devices enslaved to a VRF device
   add the master option to the ip command:
       $ ip [-6] neigh show vrf NAME
       $ ip [-6] neigh show master NAME

   For example:
   $  ip neigh show vrf red
   10.2.1.254 dev eth1 lladdr a6:d9:c7:4f:06:23 REACHABLE
   10.2.2.254 dev eth2 lladdr 5e:54:01:6a:ee:80 REACHABLE

   $ ip -6 neigh show vrf red
   2002:1::64 dev eth1 lladdr a6:d9:c7:4f:06:23 REACHABLE


6. Show Addresses for a VRF

   To show addresses for interfaces associated with a VRF add the master
   option to the ip command:
       $ ip addr show vrf NAME
       $ ip addr show master NAME

   For example:
   $ ip addr show vrf red
   3: eth1: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast master red state UP group default qlen 1000
       link/ether 02:00:00:00:02:02 brd ff:ff:ff:ff:ff:ff
       inet 10.2.1.2/24 brd 10.2.1.255 scope global eth1
          valid_lft forever preferred_lft forever
       inet6 2002:1::2/120 scope global
          valid_lft forever preferred_lft forever
       inet6 fe80::ff:fe00:202/64 scope link
          valid_lft forever preferred_lft forever
   4: eth2: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast master red state UP group default qlen 1000
       link/ether 02:00:00:00:02:03 brd ff:ff:ff:ff:ff:ff
       inet 10.2.2.2/24 brd 10.2.2.255 scope global eth2
          valid_lft forever preferred_lft forever
       inet6 2002:2::2/120 scope global
          valid_lft forever preferred_lft forever
       inet6 fe80::ff:fe00:203/64 scope link
          valid_lft forever preferred_lft forever
   7: eth5: <BROADCAST,MULTICAST> mtu 1500 qdisc noop master red state DOWN group default qlen 1000
       link/ether 02:00:00:00:02:06 brd ff:ff:ff:ff:ff:ff

   Or in brief format:
   $ ip -br addr show vrf red
   eth1             UP             10.2.1.2/24 2002:1::2/120 fe80::ff:fe00:202/64
   eth2             UP             10.2.2.2/24 2002:2::2/120 fe80::ff:fe00:203/64
   eth5             DOWN


7. Show Routes for a VRF

   To show routes for a VRF use the ip command to display the table associated
   with the VRF device:
       $ ip [-6] route show vrf NAME
       $ ip [-6] route show table ID

   For example:
   $ ip route show vrf red
   prohibit default
   broadcast 10.2.1.0 dev eth1  proto kernel  scope link  src 10.2.1.2
   10.2.1.0/24 dev eth1  proto kernel  scope link  src 10.2.1.2
   local 10.2.1.2 dev eth1  proto kernel  scope host  src 10.2.1.2
   broadcast 10.2.1.255 dev eth1  proto kernel  scope link  src 10.2.1.2
   broadcast 10.2.2.0 dev eth2  proto kernel  scope link  src 10.2.2.2
   10.2.2.0/24 dev eth2  proto kernel  scope link  src 10.2.2.2
   local 10.2.2.2 dev eth2  proto kernel  scope host  src 10.2.2.2
   broadcast 10.2.2.255 dev eth2  proto kernel  scope link  src 10.2.2.2

   $ ip -6 route show vrf red
   local 2002:1:: dev lo  proto none  metric 0  pref medium
   local 2002:1::2 dev lo  proto none  metric 0  pref medium
   2002:1::/120 dev eth1  proto kernel  metric 256  pref medium
   local 2002:2:: dev lo  proto none  metric 0  pref medium
   local 2002:2::2 dev lo  proto none  metric 0  pref medium
   2002:2::/120 dev eth2  proto kernel  metric 256  pref medium
   local fe80:: dev lo  proto none  metric 0  pref medium
   local fe80:: dev lo  proto none  metric 0  pref medium
   local fe80::ff:fe00:202 dev lo  proto none  metric 0  pref medium
   local fe80::ff:fe00:203 dev lo  proto none  metric 0  pref medium
   fe80::/64 dev eth1  proto kernel  metric 256  pref medium
   fe80::/64 dev eth2  proto kernel  metric 256  pref medium
   ff00::/8 dev red  metric 256  pref medium
   ff00::/8 dev eth1  metric 256  pref medium
   ff00::/8 dev eth2  metric 256  pref medium


8. Route Lookup for a VRF

   A test route lookup can be done for a VRF:
       $ ip [-6] route get vrf NAME ADDRESS
       $ ip [-6] route get oif NAME ADDRESS

   For example:
   $ ip route get 10.2.1.40 vrf red
   10.2.1.40 dev eth1  table red  src 10.2.1.2
       cache

   $ ip -6 route get 2002:1::32 vrf red
   2002:1::32 from :: dev eth1  table red  proto kernel  src 2002:1::2  metric 256  pref medium


9. Removing Network Interface from a VRF

   Network interfaces are removed from a VRF by breaking the enslavement to
   the VRF device:
       $ ip link set dev NAME nomaster

   Connected routes are moved back to the default table and local entries are
   moved to the local table.

   For example:
   $ ip link set dev eth0 nomaster

--------------------------------------------------------------------------------

Commands used in this example:

cat >> /etc/iproute2/rt_tables.d/vrf.conf <<EOF
1  mgmt
10 red
66 blue
81 green
EOF

function vrf_create
{
    VRF=$1
    TBID=$2

    # create VRF device
    ip link add ${VRF} type vrf table ${TBID}

    if [ "${VRF}" != "mgmt" ]; then
        ip route add table ${TBID} unreachable default
    fi
    ip link set dev ${VRF} up
}

vrf_create mgmt 1
ip link set dev eth0 master mgmt

vrf_create red 10
ip link set dev eth1 master red
ip link set dev eth2 master red
ip link set dev eth5 master red

vrf_create blue 66
ip link set dev eth3 master blue

vrf_create green 81
ip link set dev eth4 master green


Interface addresses from /etc/network/interfaces:
auto eth0
iface eth0 inet static
      address 10.0.0.2
      netmask 255.255.255.0
      gateway 10.0.0.254

iface eth0 inet6 static
      address 2000:1::2
      netmask 120

auto eth1
iface eth1 inet static
      address 10.2.1.2
      netmask 255.255.255.0

iface eth1 inet6 static
      address 2002:1::2
      netmask 120

auto eth2
iface eth2 inet static
      address 10.2.2.2
      netmask 255.255.255.0

iface eth2 inet6 static
      address 2002:2::2
      netmask 120

auto eth3
iface eth3 inet static
      address 10.2.3.2
      netmask 255.255.255.0

iface eth3 inet6 static
      address 2002:3::2
      netmask 120

auto eth4
iface eth4 inet static
      address 10.2.4.2
      netmask 255.255.255.0

iface eth4 inet6 static
      address 2002:4::2
      netmask 120
Commit	Line	Data
562d897d DA	1	Virtual Routing and Forwarding (VRF)
	2	====================================
	3	The VRF device combined with ip rules provides the ability to create virtual
	4	routing and forwarding domains (aka VRFs, VRF-lite to be specific) in the
	5	Linux network stack. One use case is the multi-tenancy problem where each
	6	tenant has their own unique routing tables and in the very least need
	7	different default gateways.
	8
	9	Processes can be "VRF aware" by binding a socket to the VRF device. Packets
	10	through the socket then use the routing table associated with the VRF
	11	device. An important feature of the VRF device implementation is that it
	12	impacts only Layer 3 and above so L2 tools (e.g., LLDP) are not affected
	13	(ie., they do not need to be run in each VRF). The design also allows
	14	the use of higher priority ip rules (Policy Based Routing, PBR) to take
	15	precedence over the VRF device rules directing specific traffic as desired.
	16
	17	In addition, VRF devices allow VRFs to be nested within namespaces. For
6e076537 DA	18	example network namespaces provide separation of network interfaces at the
	19	device layer, VLANs on the interfaces within a namespace provide L2 separation
	20	and then VRF devices provide L3 separation.
562d897d DA	21
	22	Design
	23	------
	24	A VRF device is created with an associated route table. Network interfaces
	25	are then enslaved to a VRF device:
	26
	27	+-----------------------------+
	28	\| vrf-blue \| ===> route table 10
	29	+-----------------------------+
	30	\| \| \|
	31	+------+ +------+ +-------------+
	32	\| eth1 \| \| eth2 \| ... \| bond1 \|
	33	+------+ +------+ +-------------+
	34	\| \|
	35	+------+ +------+
	36	\| eth8 \| \| eth9 \|
	37	+------+ +------+
	38
	39	Packets received on an enslaved device and are switched to the VRF device
6e076537 DA	40	in the IPv4 and IPv6 processing stacks giving the impression that packets
	41	flow through the VRF device. Similarly on egress routing rules are used to
	42	send packets to the VRF device driver before getting sent out the actual
	43	interface. This allows tcpdump on a VRF device to capture all packets into
	44	and out of the VRF as a whole.[1] Similarly, netfilter[2] and tc rules can be
	45	applied using the VRF device to specify rules that apply to the VRF domain
	46	as a whole.
562d897d DA	47
	48	[1] Packets in the forwarded state do not flow through the device, so those
	49	packets are not seen by tcpdump. Will revisit this limitation in a
	50	future release.
	51
6e076537 DA	52	[2] Iptables on ingress supports PREROUTING with skb->dev set to the real
	53	ingress device and both INPUT and PREROUTING rules with skb->dev set to
	54	the VRF device. For egress POSTROUTING and OUTPUT rules can be written
	55	using either the VRF device or real egress device.
562d897d DA	56
	57	Setup
	58	-----
	59	1. VRF device is created with an association to a FIB table.
	60	e.g, ip link add vrf-blue type vrf table 10
	61	ip link set dev vrf-blue up
	62
6e076537 DA	63	2. An l3mdev FIB rule directs lookups to the table associated with the device.
	64	A single l3mdev rule is sufficient for all VRFs. The VRF device adds the
	65	l3mdev rule for IPv4 and IPv6 when the first device is created with a
	66	default preference of 1000. Users may delete the rule if desired and add
	67	with a different priority or install per-VRF rules.
	68
	69	Prior to the v4.8 kernel iif and oif rules are needed for each VRF device:
562d897d DA	70	ip ru add oif vrf-blue table 10
	71	ip ru add iif vrf-blue table 10
	72
6e076537 DA	73	3. Set the default route for the table (and hence default route for the VRF).
6e076537 DA	74	ip route add table 10 unreachable default
562d897d	75
6e076537 DA	76	4. Enslave L3 interfaces to a VRF device.
6e076537 DA	77	ip link set dev eth1 master vrf-blue
562d897d DA	78
	79	Local and connected routes for enslaved devices are automatically moved to
	80	the table associated with VRF device. Any additional routes depending on
6e076537 DA	81	the enslaved device are dropped and will need to be reinserted to the VRF
	82	FIB table following the enslavement.
	83
	84	The IPv6 sysctl option keep_addr_on_down can be enabled to keep IPv6 global
	85	addresses as VRF enslavement changes.
	86	sysctl -w net.ipv6.conf.all.keep_addr_on_down=1
562d897d	87
6e076537 DA	88	5. Additional VRF routes are added to associated table.
6e076537 DA	89	ip route add table 10 ...
562d897d DA	90
	91
	92	Applications
	93	------------
	94	Applications that are to work within a VRF need to bind their socket to the
	95	VRF device:
	96
	97	setsockopt(sd, SOL_SOCKET, SO_BINDTODEVICE, dev, strlen(dev)+1);
	98
	99	or to specify the output device using cmsg and IP_PKTINFO.
	100
6e076537 DA	101	TCP services running in the default VRF context (ie., not bound to any VRF
	102	device) can work across all VRF domains by enabling the tcp_l3mdev_accept
	103	sysctl option:
	104	sysctl -w net.ipv4.tcp_l3mdev_accept=1
562d897d	105
6e076537 DA	106	netfilter rules on the VRF device can be used to limit access to services
	107	running in the default VRF context as well.
	108
	109	The default VRF does not have limited scope with respect to port bindings.
	110	That is, if a process does a wildcard bind to a port in the default VRF it
	111	owns the port across all VRF domains within the network namespace.
4b418bff DA	112
	113	################################################################################
	114
	115	Using iproute2 for VRFs
	116	=======================
6e076537 DA	117	iproute2 supports the vrf keyword as of v4.7. For backwards compatibility this
	118	section lists both commands where appropriate -- with the vrf keyword and the
	119	older form without it.
4b418bff DA	120
	121	1. Create a VRF
	122
	123	To instantiate a VRF device and associate it with a table:
	124	$ ip link add dev NAME type vrf table ID
	125
6e076537 DA	126	As of v4.8 the kernel supports the l3mdev FIB rule where a single rule
	127	covers all VRFs. The l3mdev rule is created for IPv4 and IPv6 on first
	128	device create.
4b418bff DA	129
	130	2. List VRFs
	131
	132	To list VRFs that have been created:
	133	$ ip [-d] link show type vrf
	134	NOTE: The -d option is needed to show the table id
	135
	136	For example:
	137	$ ip -d link show type vrf
6e076537	138	11: mgmt: <NOARP,MASTER,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP mode DEFAULT group default qlen 1000
4b418bff DA	139	link/ether 72:b3:ba:91:e2:24 brd ff:ff:ff:ff:ff:ff promiscuity 0
4b418bff DA	140	vrf table 1 addrgenmode eui64
6e076537	141	12: red: <NOARP,MASTER,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP mode DEFAULT group default qlen 1000
4b418bff DA	142	link/ether b6:6f:6e:f6:da:73 brd ff:ff:ff:ff:ff:ff promiscuity 0
4b418bff DA	143	vrf table 10 addrgenmode eui64
6e076537	144	13: blue: <NOARP,MASTER,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP mode DEFAULT group default qlen 1000
4b418bff DA	145	link/ether 36:62:e8:7d:bb:8c brd ff:ff:ff:ff:ff:ff promiscuity 0
4b418bff DA	146	vrf table 66 addrgenmode eui64
6e076537	147	14: green: <NOARP,MASTER,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP mode DEFAULT group default qlen 1000
4b418bff DA	148	link/ether e6:28:b8:63:70:bb brd ff:ff:ff:ff:ff:ff promiscuity 0
	149	vrf table 81 addrgenmode eui64
	150
	151
	152	Or in brief output:
	153
	154	$ ip -br link show type vrf
6e076537 DA	155	mgmt UP 72:b3:ba:91:e2:24 <NOARP,MASTER,UP,LOWER_UP>
	156	red UP b6:6f:6e:f6:da:73 <NOARP,MASTER,UP,LOWER_UP>
	157	blue UP 36:62:e8:7d:bb:8c <NOARP,MASTER,UP,LOWER_UP>
	158	green UP e6:28:b8:63:70:bb <NOARP,MASTER,UP,LOWER_UP>
4b418bff DA	159
	160
	161	3. Assign a Network Interface to a VRF
	162
	163	Network interfaces are assigned to a VRF by enslaving the netdevice to a
	164	VRF device:
6e076537	165	$ ip link set dev NAME master NAME
4b418bff DA	166
	167	On enslavement connected and local routes are automatically moved to the
	168	table associated with the VRF device.
	169
	170	For example:
6e076537	171	$ ip link set dev eth0 master mgmt
4b418bff DA	172
	173
	174	4. Show Devices Assigned to a VRF
	175
	176	To show devices that have been assigned to a specific VRF add the master
	177	option to the ip command:
6e076537 DA	178	$ ip link show vrf NAME
6e076537 DA	179	$ ip link show master NAME
4b418bff DA	180
4b418bff DA	181	For example:
6e076537 DA	182	$ ip link show vrf red
6e076537 DA	183	3: eth1: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast master red state UP mode DEFAULT group default qlen 1000
4b418bff	184	link/ether 02:00:00:00:02:02 brd ff:ff:ff:ff:ff:ff
6e076537	185	4: eth2: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast master red state UP mode DEFAULT group default qlen 1000
4b418bff	186	link/ether 02:00:00:00:02:03 brd ff:ff:ff:ff:ff:ff
6e076537	187	7: eth5: <BROADCAST,MULTICAST> mtu 1500 qdisc noop master red state DOWN mode DEFAULT group default qlen 1000
4b418bff DA	188	link/ether 02:00:00:00:02:06 brd ff:ff:ff:ff:ff:ff
	189
	190
	191	Or using the brief output:
484f674b	192	$ ip -br link show vrf red
4b418bff DA	193	eth1 UP 02:00:00:00:02:02 <BROADCAST,MULTICAST,UP,LOWER_UP>
	194	eth2 UP 02:00:00:00:02:03 <BROADCAST,MULTICAST,UP,LOWER_UP>
	195	eth5 DOWN 02:00:00:00:02:06 <BROADCAST,MULTICAST>
	196
	197
	198	5. Show Neighbor Entries for a VRF
	199
	200	To list neighbor entries associated with devices enslaved to a VRF device
	201	add the master option to the ip command:
6e076537 DA	202	$ ip [-6] neigh show vrf NAME
6e076537 DA	203	$ ip [-6] neigh show master NAME
4b418bff DA	204
4b418bff DA	205	For example:
6e076537	206	$ ip neigh show vrf red
4b418bff DA	207	10.2.1.254 dev eth1 lladdr a6:d9:c7:4f:06:23 REACHABLE
	208	10.2.2.254 dev eth2 lladdr 5e:54:01:6a:ee:80 REACHABLE
	209
484f674b DA	210	$ ip -6 neigh show vrf red
484f674b DA	211	2002:1::64 dev eth1 lladdr a6:d9:c7:4f:06:23 REACHABLE
4b418bff DA	212
	213
	214	6. Show Addresses for a VRF
	215
	216	To show addresses for interfaces associated with a VRF add the master
	217	option to the ip command:
6e076537 DA	218	$ ip addr show vrf NAME
6e076537 DA	219	$ ip addr show master NAME
4b418bff DA	220
4b418bff DA	221	For example:
6e076537 DA	222	$ ip addr show vrf red
6e076537 DA	223	3: eth1: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast master red state UP group default qlen 1000
4b418bff DA	224	link/ether 02:00:00:00:02:02 brd ff:ff:ff:ff:ff:ff
	225	inet 10.2.1.2/24 brd 10.2.1.255 scope global eth1
	226	valid_lft forever preferred_lft forever
	227	inet6 2002:1::2/120 scope global
	228	valid_lft forever preferred_lft forever
	229	inet6 fe80::ff:fe00:202/64 scope link
	230	valid_lft forever preferred_lft forever
6e076537	231	4: eth2: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast master red state UP group default qlen 1000
4b418bff DA	232	link/ether 02:00:00:00:02:03 brd ff:ff:ff:ff:ff:ff
	233	inet 10.2.2.2/24 brd 10.2.2.255 scope global eth2
	234	valid_lft forever preferred_lft forever
	235	inet6 2002:2::2/120 scope global
	236	valid_lft forever preferred_lft forever
	237	inet6 fe80::ff:fe00:203/64 scope link
	238	valid_lft forever preferred_lft forever
6e076537	239	7: eth5: <BROADCAST,MULTICAST> mtu 1500 qdisc noop master red state DOWN group default qlen 1000
4b418bff DA	240	link/ether 02:00:00:00:02:06 brd ff:ff:ff:ff:ff:ff
	241
	242	Or in brief format:
6e076537	243	$ ip -br addr show vrf red
4b418bff DA	244	eth1 UP 10.2.1.2/24 2002:1::2/120 fe80::ff:fe00:202/64
	245	eth2 UP 10.2.2.2/24 2002:2::2/120 fe80::ff:fe00:203/64
	246	eth5 DOWN
	247
	248
	249	7. Show Routes for a VRF
	250
	251	To show routes for a VRF use the ip command to display the table associated
	252	with the VRF device:
6e076537	253	$ ip [-6] route show vrf NAME
4b418bff DA	254	$ ip [-6] route show table ID
	255
	256	For example:
6e076537	257	$ ip route show vrf red
4b418bff DA	258	prohibit default
	259	broadcast 10.2.1.0 dev eth1 proto kernel scope link src 10.2.1.2
	260	10.2.1.0/24 dev eth1 proto kernel scope link src 10.2.1.2
	261	local 10.2.1.2 dev eth1 proto kernel scope host src 10.2.1.2
	262	broadcast 10.2.1.255 dev eth1 proto kernel scope link src 10.2.1.2
	263	broadcast 10.2.2.0 dev eth2 proto kernel scope link src 10.2.2.2
	264	10.2.2.0/24 dev eth2 proto kernel scope link src 10.2.2.2
	265	local 10.2.2.2 dev eth2 proto kernel scope host src 10.2.2.2
	266	broadcast 10.2.2.255 dev eth2 proto kernel scope link src 10.2.2.2
	267
6e076537	268	$ ip -6 route show vrf red
4b418bff DA	269	local 2002:1:: dev lo proto none metric 0 pref medium
	270	local 2002:1::2 dev lo proto none metric 0 pref medium
	271	2002:1::/120 dev eth1 proto kernel metric 256 pref medium
	272	local 2002:2:: dev lo proto none metric 0 pref medium
	273	local 2002:2::2 dev lo proto none metric 0 pref medium
	274	2002:2::/120 dev eth2 proto kernel metric 256 pref medium
	275	local fe80:: dev lo proto none metric 0 pref medium
	276	local fe80:: dev lo proto none metric 0 pref medium
	277	local fe80::ff:fe00:202 dev lo proto none metric 0 pref medium
	278	local fe80::ff:fe00:203 dev lo proto none metric 0 pref medium
	279	fe80::/64 dev eth1 proto kernel metric 256 pref medium
	280	fe80::/64 dev eth2 proto kernel metric 256 pref medium
6e076537	281	ff00::/8 dev red metric 256 pref medium
4b418bff DA	282	ff00::/8 dev eth1 metric 256 pref medium
	283	ff00::/8 dev eth2 metric 256 pref medium
	284
	285
	286	8. Route Lookup for a VRF
	287
6e076537 DA	288	A test route lookup can be done for a VRF:
	289	$ ip [-6] route get vrf NAME ADDRESS
	290	$ ip [-6] route get oif NAME ADDRESS
4b418bff DA	291
4b418bff DA	292	For example:
6e076537 DA	293	$ ip route get 10.2.1.40 vrf red
6e076537 DA	294	10.2.1.40 dev eth1 table red src 10.2.1.2
4b418bff DA	295	cache
4b418bff DA	296
6e076537 DA	297	$ ip -6 route get 2002:1::32 vrf red
6e076537 DA	298	2002:1::32 from :: dev eth1 table red proto kernel src 2002:1::2 metric 256 pref medium
4b418bff DA	299
	300
	301	9. Removing Network Interface from a VRF
	302
	303	Network interfaces are removed from a VRF by breaking the enslavement to
	304	the VRF device:
	305	$ ip link set dev NAME nomaster
	306
	307	Connected routes are moved back to the default table and local entries are
	308	moved to the local table.
	309
	310	For example:
	311	$ ip link set dev eth0 nomaster
	312
	313	--------------------------------------------------------------------------------
	314
	315	Commands used in this example:
	316
6e076537 DA	317	cat >> /etc/iproute2/rt_tables.d/vrf.conf <<EOF
	318	1 mgmt
	319	10 red
	320	66 blue
	321	81 green
4b418bff DA	322	EOF
	323
	324	function vrf_create
	325	{
	326	VRF=$1
	327	TBID=$2
4b418bff	328
6e076537 DA	329	# create VRF device
6e076537 DA	330	ip link add ${VRF} type vrf table ${TBID}
4b418bff DA	331
4b418bff DA	332	if [ "${VRF}" != "mgmt" ]; then
6e076537	333	ip route add table ${TBID} unreachable default
4b418bff	334	fi
6e076537	335	ip link set dev ${VRF} up
4b418bff DA	336	}
	337
	338	vrf_create mgmt 1
6e076537	339	ip link set dev eth0 master mgmt
4b418bff DA	340
4b418bff DA	341	vrf_create red 10
6e076537 DA	342	ip link set dev eth1 master red
	343	ip link set dev eth2 master red
	344	ip link set dev eth5 master red
4b418bff DA	345
4b418bff DA	346	vrf_create blue 66
6e076537	347	ip link set dev eth3 master blue
4b418bff DA	348
4b418bff DA	349	vrf_create green 81
6e076537	350	ip link set dev eth4 master green
4b418bff DA	351
	352
	353	Interface addresses from /etc/network/interfaces:
	354	auto eth0
	355	iface eth0 inet static
	356	address 10.0.0.2
	357	netmask 255.255.255.0
	358	gateway 10.0.0.254
	359
	360	iface eth0 inet6 static
	361	address 2000:1::2
	362	netmask 120
	363
	364	auto eth1
	365	iface eth1 inet static
	366	address 10.2.1.2
	367	netmask 255.255.255.0
	368
	369	iface eth1 inet6 static
	370	address 2002:1::2
	371	netmask 120
	372
	373	auto eth2
	374	iface eth2 inet static
	375	address 10.2.2.2
	376	netmask 255.255.255.0
	377
	378	iface eth2 inet6 static
	379	address 2002:2::2
	380	netmask 120
	381
	382	auto eth3
	383	iface eth3 inet static
	384	address 10.2.3.2
	385	netmask 255.255.255.0
	386
	387	iface eth3 inet6 static
	388	address 2002:3::2
	389	netmask 120
	390
	391	auto eth4
	392	iface eth4 inet static
	393	address 10.2.4.2
	394	netmask 255.255.255.0
	395
	396	iface eth4 inet6 static
	397	address 2002:4::2
	398	netmask 120