BelAir20E User Guide
BelAir20E Auto-configuration
April 2, 2012
Confidential
Document Number BDTM02201-A01 Standard
• DNS server IP addresses. Up to two DNS servers are supported. See
“Configuring the Domain Name System Lookup Service” on page 48
.
• IP address for a time server. Two time servers are supported for use by the
SNTP service. See
“Managing an SNTP Server” on page 52
• time offset value used by the SNTP service. See
.
Through DHCP Option 43, the BelAir20E provides the DHCP server with the
following parameters about the itself:
• assembly code, as shown with the
/system/show phyinv
command
• serial number, as shown with the
/system/show phyinv
command
• MAC address
• version of the active software load, as shown with the
/system/show loads
command
• GPS coordinates, as shown with the
/system/show coordinates
command
• switch name, as shown with the
/system/show system-id
command
• custom field 1, as shown with the
/system/show custom fields
command
You can use the information from DHCP Option 55 to configure the BelAir20E
management interface or one of its VLAN interfaces.
After the BelAir20E receives these parameters, it configures the interface in
question. At startup, it downloads the script file from the TFTP server and
executes it.
DHCP options can only be enabled for one interface. For example, if you
enable DHCP options for the management interface, you are prevented from
enabling them for a VLAN interface until you first disable them for the
management interface.
By default, the BelAir20E accepts all parameters provided by the DHCP server.
However, you can configure the BelAir20E to accept or reject any individual
parameter. By accepting only specific parameters, you can control how much of
the BelAir20E is auto-configured. For example, if you do not want to use a
script file from the TFTP server, you can set the
accept-tftp-download
parameter to
disabled
. See