8. Lagopus software switch datastore and DSL syntax

This section describes how Lagopus software switch stores configuration data in it’s datastore at runtime, and explain each parameters used in DSL syntax configuration file which is loaded to datastore at boot time.

There are two types of syntax (format) used to describe configuration of Lagopus software switch. Refer to Configuration syntax types for details about both syntax.

8.1. datastore overview

“Lagopus datastore” is a database where configuration, and other data (ex: flows) used at runtime are stored.


This diagram shows how datastore interacts with configuration files (lagopus.conf, lagopus.dsl) and lagosh command.

  • $HOME/.lagopus.conf.d/*.conf (ex: lagopus.conf) are written in lagosh configuration syntax.
  • /usr/loca/etc/lagopus/*.dsl (ex: lagopus.dsl) are written in DSL syntax.
  • Since datastore can only read files in DSL syntax, lagosh will translate *.conf file to DSL syntax while communicating with lagopus datastore via TCP.
  • lagopus will read *.dsl directly from the file at boot time.
    • Use -C filename or --config filename option to specify configuration file. (DSL format)
    • If not specified, lagopus will load /usr/loca/etc/lagopus/lagopus.dsl

8.1.1. lagosh operation and datastore

Instead of editing *.dsl file directly, you can edit/commit/save configuration using lagosh.

Refer to Using Lagopus CLI (lagosh) for detailed explanation about lagosh configuration commands.


  • Start lagosh and enter configuration mode.

    $ lagosh
    Lagosh> configure
  • Configure# edit will create working file under $HOME/.lagopus.conf.d/

    • edit file in lagosh configuration syntax.
  • Configure# commit will apply changes to lagopus running configuration (datastore).

  • Configure# save will write running configuration to /usr/local/etc/lagopus/lagopus.dsl in DSL syntax.

8.2. Configuration syntax types

There are two types of syntax (format) used to describe configuration of Lagopus software switch.

  • configuration syntax

    • Used in *.conf files.
    • Used when editing via lagosh.
  • DSL syntax

    • Used in *.dsl files.
    • Used by lagopus and it’s datastore.

    “configuration syntax” consists of object-name, identifier, and attribute value pair. Some object-name may not have identifier.

      [identifier] {
        <attribute value>;
    # example:
    interface {
            interface01 {
                    type ethernet-rawsock;
                    device eth1;
                    mtu 1500;

In “DSL syntax”, each line describes single configuration command.

<object-name> [identifier] [operation] <-attribute value> ...

# example:
interface interface01 create -type ethernet-rawsock -device eth1 -mtu 1500 -ip-addr

Refer to Configurable objects and DSL syntax for details about DSL syntax.

8.2.1. Converting between .conf and .dsl syntax

By using --dsl-encode --dsl-decode option, you can convert between .conf and .dsl syntax.


  • .conf to .dsl

    $ head .lagopus.conf.d/lagopus.conf
    log {
            ident lagopus;
            debuglevel 0;
            packetdump "";
    datastore {
            port 12345;
            protocol tcp;
    $ lagosh --dsl-encode .lagopus.conf.d/lagopus.conf
    log -syslog -ident lagopus -debuglevel 0 -packetdump ""
    datastore -addr -port 12345 -protocol tcp -tls false
    agent -channelq-size 1000 -channelq-max-batches 1000
    ... snip ...
  • .dsl to .conf

    $ head /usr/local/etc/lagopus/lagopus.dsl
    # all the log objects' attribute
    log -syslog -ident lagopus -debuglevel 0
    log -packetdump ""
    # all the datastore objects' attribute
    datastore -addr -port 12345 -protocol tcp -tls false
    # all the agent objects' attribute
    agent -channelq-size 1000 -channelq-max-batches 1000
    $ lagosh --dsl-decode /usr/local/etc/lagopus/lagopus.dsl
    log {
            ident lagopus;
            debuglevel 0;
            packetdump "";
    datastore {
            port 12345;
            protocol tcp;
            tls false;
    agent {
            channelq-size 1000;
            channelq-max-batches 1000;
    ... snip ...

8.3. Configurable objects and DSL syntax

This diagram shows overview of configurable objects of lagopus. Attributes of major configurable objects are described below.


8.3.1. log object

“log object” sets log output destination and level.

log <attribute value> ...

# example:
log -syslog -ident lagopus -debuglevel 0
log -file /home/user/lagopus.log -debuglevel 0
  • -syslog Set log destination to syslog. takes no value.
  • -file Set log destination to file.
    • You can set two lines each specifying -syslog and -file, but cannot use both attributes in one line.
  • -ident Only with -syslog. char string ident used in syslog entry. default lagopus.
  • -debuglevel Takes value of 0 ~ MAXIMUM_DBGLVL(UINT16_MAX). default 0.
    • check lagopus_msg_debug in source code for usage of debuglevel.

8.3.2. datastore object

“datastore object” sets parameters to connect to lagopus datastore.

datastore <attribute value> ...
# example:
datastore -addr -port 12345 -protocol tcp -tls false
  • -addr address of the datastore process.
  • -port tcp port the datastore process listens to.
  • -protocol protocol used to connect to datastore. tcp or tcp6.
  • -tls use TLS or not. false or true.

8.3.3. tls object

“tls object” sets parameters related to TLS.

tsl <attribute value> ...

# example:
tls -cert-file /usr/local/etc/lagopus/catls.pem -private-key /usr/local/etc/lagopus/key.pem -certificate-store /usr/local/etc/lagopus -trust-point-conf /usr/local/etc/lagopus/check.conf
  • -cert-file location of cert file. (.pem)
  • -private-key location of key file. (.pem)
  • -certificate-store location to store certificates.
  • -trust-point-conf location of trust-point-conf file. (.conf)

8.3.4. policer-action object

“policer-action object” sets type of policer action.

policer-action <policer-action-identifier> create <attribute value>

# example:
policer-action pa01 create -type discard
  • policer-action-identifier Name to identify the policer-action
  • -type Type of policer action. Currently type discard is only availble.

8.3.5. policer object

“policer object” sets policer parameters.

policer <policer-identifier> create <attribute value> ...

# example:
policer policer01 create -action pa01 -bandwidth-limit 10000 -burst-size-limit 11000 -bandwidth-percent 20
  • policer-identifier Name to identify the policer.
  • -action Name of policer-action associated with the policer.
  • -bandwidth-limit
  • -burst-size-limit
  • -bandwidth-percent

8.3.6. queue object

“queue object” sets parameters of queues used by OpenFlow set-queue action.

queue <queue-identifier> create <attribute value> ...

# example:
queue queue01 create -type two-rate -id 1 -priority 50
  • queue-identifier Name to identify the queue.
  • -type Type of queue. single-rate or two-rate.
  • -id ID used in OpenFlow set-queue action.
  • -priority Nonnegative integer, 0 ~ 65535(UINT16_MAX).
    • Packets will be scheduled on each port using weighted round robin based on ratio of priority of queues.
  • -color Behavior based on color. color-aware or color-blind.
  • Optional options for both single-rate and two-rate
    • -committed-burst-size CBS in bytes.
    • -committed-information-rate CIR in bps.
  • Optional option for single-rate
    • -excess-burst-size EBS in bytes.
  • Optional options for two-rate
    • -peak-burst-size PBS in bytes.
    • -peak-information-rate PIR in bps.

8.3.7. interface object

“interface object” sets parameters of interface.

interface <interface-identifier> create <attribute value> ...

# example:
interface interface01 create -type ethernet-rawsock -device eth1 -mtu 1500 -ip-addr
interface interface01 create -type ethernet-dpdk-phy -port-number 0
  • interface-identifier Name to identify the interface.
  • -type Type of the interface. One of below.
    • ethernet-dpdk-phy
    • ethernet-dpdk-vdev
    • ethernet-rawsock
    • gre
    • nvgre
    • vxlan
    • vhost-user
  • -device Name of the device associated with the interface. PCI ID for dpdk.
  • -port-number DPDK port number. Only used by dpdk.
  • -mtu MTU of the interface.
  • -ip-addr IP address of the interface.


Either -device or -port-number should be specified per line, not both.

8.3.8. port object

“port object” sets port and interface assosication.

port <port-identifier> create <attribute value>

# example:
port port01 create -interface interface01
  • port-identifier Name to identify the port.
  • -interface interface-identifier assosiated with the port.
  • -policer policer-identifier assosiated with the port.
  • -queue queue-identifier assosiated with the port.

8.3.9. channel object

“channel object” sets parameters of channel used to communicate with OpenFlow controller.

channel <channel-identifier> create <attribute value> ...

# example:
channel channel01 create -dst-addr -dst-port 6633 -local-addr -local-port 0 -protocol tcp
  • channel-identifier Name to identify the channel
  • -dst-addr IP address of the controller
  • -dst-port tcp port number of the controller
  • -local-addr source IP address used when connecting to controller
  • -local-port tcp port used when connecting to controller. 0 = automatically assigned.
  • -protocol protocol used when connecting to controller. tcp or tls.

8.3.10. controller object

“controller object” sets parameters related to OpenFlow controller.

controller <controller-identifier> create <attribute value> ...

# example:
controller controller01 create -channel channel01 -role equal -connection-type main
  • controller-identifier Name to identify the controller.
  • -channel channel-identifier used to connect to the controller.
  • -role Role of the controller. master, slave or equal.
  • -connection-type Controller connection type. main or auxiliary.

8.3.11. bridge object

“bridge object” sets parameters of bridge.

bridge <bridge-identifier> create <attribute value> ...

# example:
bridge bridge01 create -dpid 1 -controller controller01 -port port01 1 -port port02 2 -port port03 3 -fail-mode standalone
  • bridge-identifier Name to identify the bridge.
  • -dpid Datapath ID. Nonnegative integer.
  • -controller Name of controller (s) assosiated with the bridge.
  • -port <port-identifier> <openflow-port-id> Port name and OpenFlow port ID pair(s) assoiated with the bridge.
    • port-identifier Name of the port defined in port object.
    • openflow-port-id Port ID to be used in OpenFlow protocol. Nonnegative integer.
  • -fail-mode Mode when connection to controller was failed. secure or standalone.
  • Other optional options.
    • -flow-statistics
    • -group-statistics
    • -port-statistics
    • -queue-statistics
    • -table-statistics
    • -reassemble-ip-fragments
    • -max-buffered-packets
    • -max-ports
    • -max-tables
    • -max-flows
    • -block-looping-ports
    • -action-type
    • -instruction-type
    • -reserved-port-type
    • -group-type
    • -group-capability
    • -packet-inq-size
    • -packet-inq-max-batches
    • -up-streamq-size
    • -up-streamq-max-batches
    • -down-streamq-size
    • -down-streamq-max-batches