Manpages

NAME

ovn-nb - OVN_Northbound database schema

This database is the interface between OVN and the cloud management system (CMS), such as OpenStack, running above it. The CMS produces almost all of the contents of the database. The ovn-northd program monitors the database contents, transforms it, and stores it into the OVN_Southbound database.

We generally speak of ’’the’’ CMS, but one can imagine scenarios in which multiple CMSes manage different parts of an OVN deployment.

External IDs
Each of the tables in this database contains a special column, named external_ids. This column has the same form and purpose each place it appears.

external_ids: map of string-string pairs

Key-value pairs for use by the CMS. The CMS might use certain pairs, for example, to identify entities in its own configuration that correspond to those in this database.

TABLE SUMMARY

The following list summarizes the purpose of each of the tables in the OVN_Northbound database. Each table is described in more detail on a later page.

Logical_Switch

L2 logical switch

Logical_Switch_Port

L2 logical switch port

Address_Set

Address Sets

Port_Group

Port Groups

Load_Balancer

load balancer

Logical_Router

L3 logical router

Meter_Band

Band for meter entries

Logical_Router_Port

L3 logical router port

Logical_Router_Static_Route

Logical router static routes

DHCP_Options

DHCP options

Connection

OVSDB client connections.

Gateway_Chassis

Gateway_Chassis configuration.

NB_Global TABLE

Northbound configuration for an OVN system. This table must have exactly one row.

Summary:
Status:

Common Columns:

Common options:

Options for configuring BFD:

options : bfd-decay-min-rx

optional string

Connection Options:

Security Configurations:

Details:

Status:

These columns allow a client to track the overall configuration state of the system.
nb_cfg: integer

Sequence number for client to increment. When a client modifies any part of the northbound database configuration and wishes to wait for ovn-northd and possibly all of the hypervisors to finish applying the changes, it may increment this sequence number.

sb_cfg: integer

Sequence number that ovn-northd sets to the value of nb_cfg after it finishes applying the corresponding configuration changes to the OVN_Southbound database.

hv_cfg: integer

Sequence number that ovn-northd sets to the smallest sequence number of all the chassis in the system, as reported in the Chassis table in the southbound database. Thus, hv_cfg equals nb_cfg if all chassis are caught up with the northbound configuration (which may never happen, if any chassis is down). This value can regress, if a chassis was removed from the system and rejoins before catching up.

Common Columns:

external_ids: map of string-string pairs

See External IDs at the beginning of this document.

Common options:

options: map of string-string pairs

This column provides general key/value settings. The supported options are described individually below.

Options for configuring BFD:

These options apply when ovn-controller configures BFD on tunnels interfaces.
options : bfd-min-rx: optional string

BFD option min-rx value to use when configuring BFD on tunnel interfaces.

options : bfd-decay-min-rx: optional string

BFD option decay-min-rx value to use when configuring BFD on tunnel interfaces.

options : bfd-min-tx: optional string

BFD option min-tx value to use when configuring BFD on tunnel interfaces.

options : bfd-mult: optional string

BFD option mult value to use when configuring BFD on tunnel interfaces.

options : mac_prefix: optional string

Configure a given OUI to be used as prefix when L2 address is dynamically assigned, e.g. 00:11:22

Connection Options:

connections: set of Connections

Database clients to which the Open vSwitch database server should connect or on which it should listen, along with options for how these connections should be configured. See the Connection table for more information.

ssl: optional SSL

Global SSL configuration.

Security Configurations:

ipsec: boolean

Tunnel encryption configuration. If this column is set to be true, all OVN tunnels will be encrypted with IPsec.

Logical_Switch TABLE

Each row represents one L2 logical switch.

There are two kinds of logical switches, that is, ones that fully virtualize the network (overlay logical switches) and ones that provide simple connectivity to a physical network (bridged logical switches). They work in the same way when providing connectivity between logical ports on same chasis, but differently when connecting remote logical ports. Overlay logical switches connect remote logical ports by tunnels, while bridged logical switches provide connectivity to remote ports by bridging the packets to directly connected physical L2 segment with the help of localnet ports. Each bridged logical switch has one and only one localnet port, which has only one special address unknown.

Summary:

Naming:

external_ids : neutron:network_name

optional string

IP Address Assignment:

Common Columns:

Details:
ports: set of Logical_Switch_Ports

The logical ports connected to the logical switch.

It is an error for multiple logical switches to include the same logical port.

load_balancer: set of Load_Balancers

Load balance a virtual ip address to a set of logical port endpoint ip addresses.

acls: set of ACLs

Access control rules that apply to packets within the logical switch.

qos_rules: set of QoSs

QoS marking and metering rules that apply to packets within the logical switch.

dns_records: set of weak reference to DNSs

This column defines the DNS records to be used for resolving internal DNS queries within the logical switch by the native DNS resolver. Please see the DNS table.

Naming:

These columns provide names for the logical switch. From OVN’s perspective, these names have no special meaning or purpose other than to provide convenience for human interaction with the database. There is no requirement for the name to be unique. (For a unique identifier for a logical switch, use its row UUID.)

(Originally, name was intended to serve the purpose of a human-friendly name, but the Neutron integration used it to uniquely identify its own switch object, in the format neutron-uuid. Later on, Neutron started propagating the friendly name of a switch as external_ids:neutron:network_name. Perhaps this can be cleaned up someday.)
name: string

A name for the logical switch.

external_ids : neutron:network_name: optional string

Another name for the logical switch.

IP Address Assignment:

These options control automatic IP address management (IPAM) for ports attached to the logical switch. To enable IPAM for IPv4, set other_config:subnet and optionally other_config:exclude_ips. To enable IPAM for IPv6, set other_config:ipv6_prefix. IPv4 and IPv6 may be enabled together or separately.

To request dynamic address assignment for a particular port, use the dynamic keyword in the addresses column of the port’s Logical_Switch_Port row. This requests both an IPv4 and an IPv6 address, if IPAM for IPv4 and IPv6 are both enabled.

other_config : subnet: optional string

Set this to an IPv4 subnet, e.g. 192.168.0.0/24, to enable ovn-northd to automatically assign IP addresses within that subnet.

other_config : exclude_ips: optional string

To exclude some addresses from automatic IP address management, set this to a list of the IPv4 addresses or ..-delimited ranges to exclude. The addresses or ranges should be a subset of those in other_config:subnet.

Whether listed or not, ovn-northd will never allocate the first or last address in a subnet, such as 192.168.0.0 or 192.168.0.255 in 192.168.0.0/24.

Examples:

other_config : ipv6_prefix: optional string

Set this to an IPv6 prefix to enable ovn-northd to automatically assign IPv6 addresses using this prefix. The assigned IPv6 address will be generated using the IPv6 prefix and the MAC address (converted to an IEEE EUI64 identifier) of the port. The IPv6 prefix defined here should be a valid IPv6 address ending with ::.

Examples:

other_config : mac_only: optional string, either true or false

Value used to request to assign L2 address only if neither subnet nor ipv6_prefix are specified

Common Columns:

external_ids: map of string-string pairs

See External IDs at the beginning of this document.

Logical_Switch_Port TABLE

A port within an L2 logical switch.

Summary:
Core Features:

Options:

Options for router ports:

Options for localnet ports:

Options for l2gateway ports:

options : l2gateway-chassis

optional string

Options for vtep ports:

options : vtep-physical-switch

optional string

options : vtep-logical-switch

optional string

VMI (or VIF) Options:

options : requested-chassis

optional string

Containers:

Port State:

Addressing:

DHCP:

Naming:

external_ids : neutron:port_name

optional string

Common Columns:

Details:

Core Features:

name: string (must be unique within table)

The logical port name.

For entities (VMs or containers) that are spawned in the hypervisor, the name used here must match those used in the external_ids:iface-id in the Open_vSwitch database’s Interface table, because hypervisors use external_ids:iface-id as a lookup key to identify the network interface of that entity.

For containers that share a VIF within a VM, the name can be any unique identifier. See Containers, below, for more information.

type: string

Specify a type for this logical port. Logical ports can be used to model other types of connectivity into an OVN logical switch. The following types are defined:
(empty string)

A VM (or VIF) interface.

localnet

A connection to a locally accessible network from each ovn-controller instance. A logical switch can only have a single localnet port attached. This is used to model direct connectivity to an existing network.

localport

A connection to a local VIF. Traffic that arrives on a localport is never forwarded over a tunnel to another chassis. These ports are present on every chassis and have the same address in all of them. This is used to model connectivity to local services that run on every hypervisor.

l2gateway

A connection to a physical network.

Options:

options: map of string-string pairs

This column provides key/value settings specific to the logical port type. The type-specific options are described individually

below.

Options for router ports:

These options apply when type is router.
options : router-port: optional string

Required. The name of the Logical_Router_Port to which this logical switch port is connected.

options : nat-addresses: optional string

This is used to send gratuitous ARPs for SNAT and DNAT IP addresses via the localnet port that is attached to the same logical switch as this type router port. This option is specified on a logical switch port that is connected to a gateway router, or a logical switch port that is connected to a distributed gateway port on a logical router.

This must take one of the following forms:

This form of options:nat-addresses is valid for logical switch ports where options:router-port is the name of a port on a gateway router, or the name of a distributed gateway port.

Supported only in OVN 2.8 and later. Earlier versions required NAT addresses to be manually synchronized.

Ethernet address followed by one or more IPv4 addresses

Example: 80:fa:5b:06:72:b7 158.36.44.22 158.36.44.24. This would result in generation of gratuitous ARPs for IP addresses 158.36.44.22 and 158.36.44.24 with a MAC address of 80:fa:5b:06:72:b7.

This form of options:nat-addresses is only valid for logical switch ports where options:router-port is the name of a port on a gateway router.

Options for localnet ports:

These options apply when type is localnet.
options : network_name: optional string

Required. The name of the network to which the localnet port is connected. Each hypervisor, via ovn-controller, uses its local

configuration to determine exactly how to connect to this locally accessible network.

Options for l2gateway ports:

These options apply when type is l2gateway.
options : network_name: optional string

Required. The name of the network to which the l2gateway port is connected. The L2 gateway, via ovn-controller, uses its local configuration to determine exactly how to connect to this network.

options : l2gateway-chassis: optional string

Required. The chassis on which the l2gateway logical port should be bound to. ovn-controller running on the defined chassis will connect this logical port to the physical network.

Options for vtep ports:

These options apply when type is vtep.
options : vtep-physical-switch: optional string

Required. The name of the VTEP gateway.

options : vtep-logical-switch: optional string

Required. A logical switch name connected by the VTEP gateway.

VMI (or VIF) Options:

These options apply to logical ports with type having (empty string)
options : requested-chassis: optional string

If set, identifies a specific chassis (by name or hostname) that is allowed to bind this port. Using this option will prevent thrashing between two chassis trying to bind the same port during a live migration. It can also prevent similar thrashing due to a mis-configuration, if a port is accidentally created on more than one chassis.

options : qos_max_rate: optional string

If set, indicates the maximum rate for data sent from this interface, in bit/s. The traffic will be shaped according to this limit.

options : qos_burst: optional string

If set, indicates the maximum burst size for data sent from this interface, in bits.

Containers:

When a large number of containers are nested within a VM, it may be too expensive to dedicate a VIF to each container. OVN can use VLAN tags to support such cases. Each container is assigned a VLAN ID and each packet that passes between the hypervisor and the VM is tagged with the appropriate ID for the container. Such VLAN IDs never appear on a physical wire, even inside a tunnel, so they need not be unique except relative to a single VM on a hypervisor.

These columns are used for VIFs that represent nested containers using shared VIFs. For VMs and for containers that have dedicated VIFs, they are empty.
parent_name: optional string

The VM interface through which the nested container sends its network traffic. This must match the name column for some other Logical_Switch_Port.

tag_request: optional integer, in range 0 to 4,095

The VLAN tag in the network traffic associated with a container’s network interface. The client can request ovn-northd to allocate a tag that is unique within the scope of a specific parent (specified in parent_name) by setting a value of 0 in this column. The allocated value is written by ovn-northd in the tag column. (Note that these tags are allocated and managed locally in ovn-northd, so they cannot be reconstructed in the event that the database is lost.) The client can also request a specific non-zero tag and ovn-northd will honor it and copy that value to the tag column.

When type is set to localnet or l2gateway, this can be set to indicate that the port represents a connection to a specific VLAN on a locally accessible network. The VLAN ID is used to match incoming traffic and is also added to outgoing traffic.

tag: optional integer, in range 1 to 4,095

The VLAN tag allocated by ovn-northd based on the contents of the tag_request column.

Port State:

up: optional boolean

This column is populated by ovn-northd, rather than by the CMS plugin as is most of this database. When a logical port is bound to a physical location in the OVN Southbound database Binding table, ovn-northd sets this column to true; otherwise, or if the port becomes unbound later, it sets it to false. This allows the CMS to wait for a VM’s (or container’s) networking to become active before it allows the VM (or container) to start.

Logical ports of router type are an exception to this rule. They are considered to be always up, that is this column is always set to true.

enabled: optional boolean

This column is used to administratively set port state. If this column is empty or is set to true, the port is enabled. If this column is set to false, the port is disabled. A disabled port has all ingress and egress traffic dropped.

Addressing:

addresses: set of strings

Addresses owned by the logical port.

Each element in the set must take one of the following forms:
Ethernet address followed by zero or more IPv4 or IPv6 addresses
(or both)

An Ethernet address defined is owned by the logical port. Like a physical Ethernet NIC, a logical port ordinarily has a single fixed Ethernet address.

When a OVN logical switch processes a unicast Ethernet frame whose destination MAC address is in a logical port’s addresses column, it delivers it only to that port, as if a MAC learning process had learned that MAC address on the port.

If IPv4 or IPv6 address(es) (or both) are defined, it indicates that the logical port owns the given IP addresses.

If IPv4 address(es) are defined, the OVN logical switch uses this information to synthesize responses to ARP requests without traversing the physical network. The OVN logical router connected to the logical switch, if any, uses this information to avoid issuing ARP requests for logical switch ports.

Note that the order here is important. The Ethernet address must be listed before the IP address(es) if defined.

Examples:
80:fa:5b:06:72:b7

This indicates that the logical port owns the above mac address.

80:fa:5b:06:72:b7 10.0.0.4 20.0.0.4

This indicates that the logical port owns the mac address and two IPv4 addresses.

80:fa:5b:06:72:b7 fdaa:15f2:72cf:0:f816:3eff:fe20:3f41

This indicates that the logical port owns the mac address and 1 IPv6 address.

80:fa:5b:06:72:b7 10.0.0.4
fdaa:15f2:72cf:0:f816:3eff:fe20:3f41

This indicates that the logical port owns the mac address and 1 IPv4 address and 1 IPv6 address.

unknown

This indicates that the logical port has an unknown set of Ethernet addresses. When an OVN logical switch processes a unicast Ethernet frame whose destination MAC address is not in any logical port’s addresses column, it delivers it to the port (or ports) whose addresses columns include unknown.

dynamic

Use this keyword to make ovn-northd generate a globally unique MAC address and choose an unused IPv4 address with the logical port’s subnet and store them in the port’s dynamic_addresses column. ovn-northd will use the subnet specified in other_config:subnet in the port’s Logical_Switch.

Ethernet address followed by keyword "dynamic"

The keyword dynamic after the MAC address indicates that ovn-northd should choose an unused IPv4 address from the logical port’s subnet and store it with the specified MAC in the port’s dynamic_addresses column. ovn-northd will use the subnet specified in other_config:subnet in the port’s Logical_Switch table.

Examples:
80:fa:5b:06:72:b7 dynamic

This indicates that the logical port owns the specified MAC address and ovn-northd should allocate an unused IPv4 address for the logical port from the corresponding logical switch subnet.

The resulting addresses are used to populate the logical switch’s destination lookup, and also for the logical switch to generate ARP and ND replies.

If the connected logical router port has a redirect-chassis specified and the logical router has rules specified in nat with external_mac, then those addresses are also used to populate the switch’s destination lookup.

Supported only in OVN 2.7 and later. Earlier versions required router addresses to be manually synchronized.

dynamic_addresses: optional string

Addresses assigned to the logical port by ovn-northd, if dynamic is specified in addresses. Addresses will be of the same format as those that populate the addresses column. Note that dynamically assigned addresses are constructed and managed locally in ovn-northd, so they cannot be reconstructed in the event that the database is lost.

port_security: set of strings

This column controls the addresses from which the host attached to the logical port (’’the host’’) is allowed to send packets and to which it is allowed to receive packets. If this column is empty, all addresses are permitted.

Each element in the set must begin with one Ethernet address. This would restrict the host to sending packets from and receiving packets to the ethernet addresses defined in the logical port’s port_security column. It also restricts the inner source MAC addresses that the host may send in ARP and IPv6 Neighbor Discovery packets. The host is always allowed to receive packets to multicast and broadcast Ethernet addresses.

Each element in the set may additionally contain one or more IPv4 or IPv6 addresses (or both), with optional masks. If a mask is given, it must be a CIDR mask. In addition to the restrictions described for Ethernet addresses above, such an element restricts the IPv4 or IPv6 addresses from which the host may send and to which it may receive packets to the specified addresses. A masked address, if the host part is zero, indicates that the host is allowed to use any address in the subnet; if the host part is nonzero, the mask simply indicates the size of the subnet. In addition:

the host is also allowed to receive packets to the broadcast address in that specified subnet.

If any IPv4 address is given, the host is additionally restricted to sending ARP packets with the specified source IPv4 address. (RARP is not restricted.)

If any IPv6 address is given, the host is additionally restricted to sending IPv6 Neighbor Discovery Solicitation or Advertisement packets with the specified source address or, for solicitations, the unspecified address.

If an element includes an IPv4 address, but no IPv6 addresses, then IPv6 traffic is not allowed. If an element includes an IPv6 address, but no IPv4 address, then IPv4 and ARP traffic is not allowed.

This column uses the same lexical syntax as the match column in the OVN Southbound database’s Pipeline table. Multiple addresses within an element may be space or comma separated.

This column is provided as a convenience to cloud management systems, but all of the features that it implements can be implemented as ACLs using the ACL table.

Examples:
80:fa:5b:06:72:b7

The host may send traffic from and receive traffic to the specified MAC address, and to receive traffic to Ethernet multicast and broadcast addresses, but not otherwise. The host may not send ARP or IPv6 Neighbor Discovery packets with inner source Ethernet addresses other than the one specified.

80:fa:5b:06:72:b7 192.168.1.10/24

This adds further restrictions to the first example. The host may send IPv4 packets from or receive IPv4 packets to only 192.168.1.10, except that it may also receive IPv4 packets to 192.168.1.255 (based on the subnet mask), 255.255.255.255, and any address in 224.0.0.0/4. The host may not send ARPs with a source Ethernet address other than 80:fa:5b:06:72:b7 or source IPv4 address other than 192.168.1.10. The host may not send or receive any IPv6 (including IPv6 Neighbor Discovery) traffic.

"80:fa:5b:12:42:ba", "80:fa:5b:06:72:b7 192.168.1.10/24"

The host may send traffic from and receive traffic to the specified MAC addresses, and to receive traffic to Ethernet multicast and broadcast addresses, but not otherwise. With MAC 80:fa:5b:12:42:ba, the host may send traffic from and receive traffic to any L3 address. With MAC 80:fa:5b:06:72:b7, the host may send IPv4 packets from or receive IPv4 packets to only 192.168.1.10, except that it may also receive IPv4 packets to 192.168.1.255 (based on the subnet mask), 255.255.255.255, and any address in 224.0.0.0/4. The host may not send or receive any IPv6 (including IPv6 Neighbor Discovery) traffic.

DHCP:

dhcpv4_options: optional weak reference to DHCP_Options

This column defines the DHCPv4 Options to be included by the ovn-controller when it replies to the DHCPv4 requests. Please see the DHCP_Options table.

dhcpv6_options: optional weak reference to DHCP_Options

This column defines the DHCPv6 Options to be included by the ovn-controller when it replies to the DHCPv6 requests. Please see the DHCP_Options table.

Naming:

external_ids : neutron:port_name: optional string

This column gives an optional human-friendly name for the port. This name has no special meaning or purpose other than to provide convenience for human interaction with the northbound database.

Neutron copies this from its own port object’s name. (Neutron ports do are not assigned human-friendly names by default, so it will often be empty.)

Common Columns:

external_ids: map of string-string pairs

See External IDs at the beginning of this document.

The ovn-northd program copies all these pairs into the external_ids column of the Port_Binding table in OVN_Southbound database.

Address_Set TABLE

Each row in this table represents a named set of addresses. An address set may contain Ethernet, IPv4, or IPv6 addresses with optional bitwise or CIDR masks. Address set may ultimately be used in ACLs to compare against fields such as ip4.src or ip6.src. A single address set must contain addresses of the same type. As an example, the following would create an address set with three IP addresses:

ovn-nbctl create Address_Set name=set1 addresses=’10.0.0.1 10.0.0.2 10.0.0.3’

Address sets may be used in the match column of the ACL table. For syntax information, see the details of the expression language used for the match column in the Logical_Flow table of the OVN_Southbound database.

Summary:

Common Columns:

Details:
name: string (must be unique within table)

A name for the address set. Names are ASCII and must match [a-zA-Z_.][a-zA-Z_.0-9]*.

addresses: set of strings

The set of addresses in string form.

Common Columns:

external_ids: map of string-string pairs

See External IDs at the beginning of this document.

Port_Group TABLE

Each row in this table represents a named group of logical switch ports.

Port groups may be used in the match column of the ACL table. For syntax information, see the details of the expression language used for the match column in the Logical_Flow table of the OVN_Southbound database.

For each port group, there are two address sets generated to the Address_Set table of the OVN_Southbound database, containing the IP addresses of the group of ports, one for IPv4, and the other for IPv6, with name being the name of the Port_Group followed by a suffix _ip4 for IPv4 and _ip6 for IPv6. The generated address sets can be used in the same way as regular address sets in the match column of the ACL table. For syntax information, see the details of the expression language used for the match column in the Logical_Flow table of the OVN_Southbound database.

Summary:

Common Columns:

Details:
name: string (must be unique within table)

A name for the port group. Names are ASCII and must match [a-zA-Z_.][a-zA-Z_.0-9]*.

ports: set of weak reference to Logical_Switch_Ports

The logical switch ports belonging to the group in uuids.

acls: set of ACLs

Access control rules that apply to the port group. Applying an ACL to a port group has the same effect as applying the ACL to all logical lswitches that the ports of the port group belong to.

Common Columns:

external_ids: map of string-string pairs

See External IDs at the beginning of this document.

Load_Balancer TABLE

Each row represents one load balancer.

Summary:

Common Columns:

Details:
name: string

A name for the load balancer. This name has no special meaning or purpose other than to provide convenience for human interaction with the ovn-nb database.

vips: map of string-string pairs

A map of virtual IP addresses (and an optional port number with : as a separator) associated with this load balancer and their corresponding endpoint IP addresses (and optional port numbers with : as separators) separated by commas. If the destination IP

address (and port number) of a packet leaving a container or a VM matches the virtual IP address (and port number) provided here as a key, then OVN will statefully replace the destination IP address by one of the provided IP address (and port number) in this map as a value. IPv4 and IPv6 addresses are supported for load balancing; however a VIP of one address family may not be mapped to a destination IP address of a different family. If specifying an IPv6 address with a port, the address portion must be enclosed in square brackets. Examples for keys are "192.168.1.4" and "[fd0f::1]:8800". Examples for value are "10.0.0.1, 10.0.0.2" and "20.0.0.10:8800, 20.0.0.11:8800".

When the Load_Balancer is added to the logical_switch, the VIP has to be in a different subnet than the one used for the logical_switch. Since VIP is in a different subnet, you should connect your logical switch to either a OVN logical router or a real router (this is because the client can now send a packet with VIP as the destination IP address and router’s mac address as the destination MAC address).

protocol: optional string, either tcp or udp

Valid protocols are tcp or udp. This column is useful when a port number is provided as part of the vips column. If this

column is empty and a port number is provided as part of vips column, OVN assumes the protocol to be tcp.

Common Columns:

external_ids: map of string-string pairs

See External IDs at the beginning of this document.

ACL TABLE

Each row in this table represents one ACL rule for a logical switch or a port group that points to it through its acls column. The action column for the highest-priority matching row in this table determines a packet’s treatment. If no row matches, packets are allowed by default. (Default-deny treatment is possible: add a rule with priority 0, 1 as

match

, and deny as action.)

Summary: