Cisco Cisco Dynamic Fabric Automation for OpenStack Troubleshooting Guide
Cisco Dynamic Fabric Automation Production Troubleshooting Guide
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VSI Discovery and Configuration Protocol:
VDP enables the association (registration) and de-association of virtual machine interfaces (VSIs) with a server-facing
leaf switch interface.
VDP makes uses of TLVs (type/length/value triplets) to carry information between a VDP Station and a VDP bridge. The
standard defines 3 sets of TLVs :
leaf switch interface.
VDP makes uses of TLVs (type/length/value triplets) to carry information between a VDP Station and a VDP bridge. The
standard defines 3 sets of TLVs :
-
The VSI manager TLV allows to address a given VSI manager or VSI database. This TLV is present in every
VDP PDUs (VDPUs) and must be the first TLV. A value of 0 means the station does not know what VSI manag-
er to use.
VDP PDUs (VDPUs) and must be the first TLV. A value of 0 means the station does not know what VSI manag-
er to use.
-
VDP association TLVs whose types are Pre-Associate, Pre-Associate with resource reservation, Associate
and De-associate. The figure below illustrates the format of the association TLVs. Of interest is the filter info
field which is a subset of VLAN ID, MAC address, group ID (segment ID) and IP address, the combination of
which is defined by the filter info format field.
and De-associate. The figure below illustrates the format of the association TLVs. Of interest is the filter info
field which is a subset of VLAN ID, MAC address, group ID (segment ID) and IP address, the combination of
which is defined by the filter info format field.
TLV type
(7 bits)
TLV
length
length
(9 bits)
Status
(1
byte)
byte)
VSI Type
ID
ID
(3 bytes)
VSI Type
Version
Version
(1 byte)
VSIID
format
format
(1 byte)
VSIID
(16
bytes)
bytes)
Filter Info
format
format
(1 byte)
Filter
Info
Info
(M
bytes)
bytes)
-
Organizationally defined TLVs, allows extending the protocol to carry organization specific information. Nexus
1000V and DFA leaf switches make use of these files to carry Virtual Machines names.
1000V and DFA leaf switches make use of these files to carry Virtual Machines names.
VSI Discovery and Configuration Protocol Sequence:
1. When a VM is activated, the VDP station (Nexus 1000V switch) passes the network information to the DFA leaf
switch through a VDP association request. The network information is carried in the filter info field of the asso-
ciation TLV. In case of segmentation-based VDP, the group ID is populated with the value of the network
segment, and the VLAN ID is set to a null value indicating the VDP station does not yet know which locally sig-
nificant VLAN ID is associated with the Layer-2 segment.
2. After receiving the association request, the leaf switch extracts the network information and automatically
configures and attaches a VLAN value to the segment ID.
3. The leaf switch then sends a response to the Cisco Nexus 1000V Series switch after the filter info field is
modified with the new VLAN information. The Cisco Nexus 1000V applies this VLAN value in the dot1q encap-
sulation of packets for that VM.
4. After a VM is successfully associated, the Nexus 1000V switch periodically sends the association TLV to the
leaf switch for a state refresh.
Timers: