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Clean Access DHCP custom options

I am trying to set up a custom DHCP scope option in a Clean Access Server. The option to do that provides a blank text box and says to enter the appropriate text for an option.

Anyone know the syntax to provide in this text box?


Re: Clean Access DHCP custom options

In the CAS management pages, click the Network tab, then the DHCP submenu link. The DHCP Status tab displays by default.

The DHCP type dropdown menu indicates the DHCP operation mode for the Clean Access Server. The options are:

a. DHCP Server - The CAS allocates client IP addresses for the untrusted (managed) network.

b. DHCP Passthrough (default)- The CAS propagates the DHCP broadcast messages across its interfaces without modification. This mode should be selected if there is an existing DHCP server on the network segment.

c. DHCP Relay - The CAS forwards messages from clients to another DHCP server. If selecting this type, wait for the page to refresh after clicking the Select DHCP Type button, then specify the external DHCP server by IP address in the Relay to DHCP Server field and click Update.

Step 3 For this example, choose DHCP Server as the operation type and click the Select DHCP Type button (note that this button toggles to Select DHCP Type and Reboot Clean Access Server after the CAS is configured as a DHCP Server).

The next step is to configure the IP pool from which client addresses are assigned using fields (i) and (j) from the CAS Installation Worksheet.

Step 4 From Device Management > CCA Servers > IPaddress > Network > DHCP, Click the Subnet List tab, then the New sublink.

step5 In the New range form, fill out the following fields:

IP Range - The IP address pool to be assigned to clients. Use field (i) and field (j) of the CAS Installation Worksheet to provide a range of addresses in the untrusted network not currently used in your environment.

Default Gateway - The IP address of the default gateway IP address passed to clients (this should be the untrusted (eth1) IP address of the CAS, field (e) of the CAS Installation Worksheet).

Default/Max Lease Time (seconds)- The default and maximum amount of time that the IP address is given to the client, in seconds (such as 3600). The default lease time is used if the client does not request a particular lease time.

DNS Suffix - The DNS suffix to be passed to clients along with the address (e.g.

DNS Servers - The address of one or more DNS servers in the client's environment. Multiple addresses should be comma-separated.

WIN Servers - The address of one or more WIN servers in the client's environment. Multiple addresses should be comma-separated.

Restrict range to VLAN ID  This option is used when more than one managed subnet is added and more than one VLAN is configured. You can leave this blank for this example.

Subnet/Netmask - Choose how the subnet and netmask values are calculated for the IP pool. Options are:

Calculate from existing managed subnets.

Calculate smallest subnet for IP range entered.

Manually enter subnet and mask  the Subnet and Netmask fields appear below if this option is selected.

For this example, select Calculate smallest subnet for IP range entered.

Step 6 When finished, click Update. If any error messages appear, correct the configuration as instructed and try creating the pool again.

Step 7 The new subnet list now appears under Device Management > CCA Servers > IPaddress > Network > DHCP > Subnet List > List.

Step 8 You can click the DHCP Status tab to display the total number of Dynamic IPs configured for the new subnet list and Available IPs remaining in the subnet list that can be assigned to clients (in the example below, only one address is assigned).

When IP addresses are assigned to clients, clicking the View MACs button (magnifying glass icon) on the DHCP Status page displays the client information.

You can verify that the DHCP module is running for a CAS by clicking the Status tab for the Clean Access Server. Make sure the DHCP Server module displays a status of Started.

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