Troubleshooting guide

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Cisco Wide Area Application Services Configuration Guide
OL-26579-01
Chapter 1 Planning Your WAAS Network
About Autoregistration and WAEs
About Autoregistration and WAEs
Autoregistration automatically configures network settings and registers WAEs with the WAAS Central
Manager device. On startup, devices running WAAS software (with the exception of the WAAS Central
Manager device itself) automatically discover the WAAS Central Manager device and register with it.
You do not need to manually configure the device. This feature is useful for large scale automated
deployments of devices. Once a WAE is registered, you configure the device remotely using the WAAS
Central Manager GUI.
In the example configuration provided in the Cisco Wide Area Application Services Quick Configuration
Guide, the autoregistration feature is disabled on the WAEs when the setup utility is used to perform the
initial configuration of the device.
Autoregistration uses a form of Dynamic Host Configuration Protocol (DHCP). For autoregistration to
function, you must have a DHCP server that is configured with the hostname of the WAAS Central
Manager and that is capable of handling vendor class option 43.
Note The form of DHCP used for autoregistration is not the same as the interface-level DHCP that is
configurable through the ip address dhcp interface configuration command. (For a description of the ip
address dhcp interface configuration command, see the Cisco Wide Area Application Services
Command Reference.)
The vendor class option (option 43) information needs to be sent to the WAAS device in the format for
encapsulated vendor-specific options as provided in RFC 2132. The relevant section of RFC 2132,
Section 8.4, is reproduced here as follows:
The encapsulated vendor-specific options field should be encoded as a sequence of
code/length/value fields of syntax identical to that of the DHCP options field with the following
exceptions:
a. There should not be a “magic cookie” field in the encapsulated vendor-specific extensions field.
b. Codes other than 0 or 255 may be redefined by the vendor within the encapsulated
vendor-specific extensions field but should conform to the tag-length-value syntax defined in
section 2.
c. Code 255 (END), if present, signifies the end of the encapsulated vendor extensions, not the end
of the vendor extensions field. If no code 255 is present, then the end of the enclosing
vendor-specific information field is taken as the end of the encapsulated vendor-specific
extensions field.
In accordance with the RFC standard, the DHCP server needs to send the WAAS Central Manager’s
hostname information in code/length/value format (code and length are single octets). The code for the
WAAS Central Manager’s hostname is 0x01. DHCP server management and configuration are not within
the scope of the autoregistration feature.
Note The WAE sends “CISCOCDN” as the vendor class identifier in option 60 to facilitate your grouping of
WAEs into device groups.
Autoregistration DHCP also requires that the following options be present in the DHCP server’s offer to
be considered valid:
• Subnet-mask (option 1)
• Routers (option 3)