Reference Guide

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For a given switch {s1}, can provide the list of ports that this service has discovered
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For two switches {s1, s2}, the service can indicate if they are "strongly connected" i.e. form
part of same cluster.
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For a given {switch, port} pair, it would indicate if they participate as a "connection point" (
if they form an 'edge port')
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For a given {switch, port} pair, this service can indicate if ingress broadcast is allowed
through 'port'
 Example: if one needs to flood out packets through a port, it can do a check using this
API to see if broadcast would be possible through this port. If this API indicates negative,
then it would mean the port is in blocked state.
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Provide hooks for interested components to get notified of topology changes
See Javadoc on page 9 for details of the API’s provided by Topology Manager.
Path Diagnostics
Path Diagnostics is a default end-user application using PathDiagnosticService API. Path Diagnostics
determines and verifies the path taken by trace packets from a source host to a destination host. The
application finds an existing flow that matches the description of the trace packet, clone it with
higher priority and add an additional action to instruct the selected switch to send this packet back
to the controller for status tally.
For REST command line API please refer to HP VAN SDN Controller Administrator Guide [9.6]
Path Daemon
Path Daemon is a path-paving application which listens for all ARP and IP PACKET_IN messages
and attempts to push flow-mods to switches along the forwarding path to ensure that such packets
get forwarded at line-rate. Path Daemon operates most optimally when the entire network is
controlled by the controller team (i.e.: no uncontrolled switches) and the switches are inter-
connected at layer 2. Each PACKET_IN message processed by Path Daemon will result in a
PACKET_OUT message and possibly a flow-mod getting pushed to one or more controlled
devices.
By default, the Path Daemon application will push flow-mods that attempt to forward traffic using
only MAC addressing and port. These flow-mods are only pushed when the ControllerManager
configuration has hybrid.mode=false. Specifically, the flow-mods will match all packets that enter a
specific switch on a specific port and they will match only packets with the source MAC address
and destination MAC address from the PACKET_IN. Optionally, the PathDaemon configuration
allows the source IP and destination IP fields to be included as matching criteria (when
layer3.forward=true).
Any packets which match the flow-mod will be forwarded to a destination port determined by Path
Daemon to get the packet to most optimally reach its intended destination. Each flow-mod is
assigned an idle timeout value, which specifies how long the flow-mod will remain in the device if
the flow-mod is not actively being used. Each flow-mod is also assigned a hard timeout value,
which specifies how long the flow-mod will remain in the device (regardless of usage). The
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