How to use DHCP option 120 in SonicWall

DHCP option 120 is described in RFC 3361 -  Dynamic Host Configuration Protocol (DHCP-for-IPv4) Option for Session Initiation Protocol (SIP) Servers.
The SIP server DHCP option carries a 32-bit (binary) IPv4 address used by the SIP client to locate a SIP server.

Resolution for SonicOS 7.X

This release includes significant user interface changes and many new features that are different from the SonicOS 6.5 and earlier firmware. The below resolution is for customers using SonicOS 7.X firmware.

How to configure option 120 on SonicWall DHCP server?

For DHCP option 120:

Available option types are:

• IP Address
• Domain name
  
• Four byte data
  
• two byte data
• one byte
• data
• String
• Boolean
• Hex string

 NOTE: For DHCP Option 120 use option type One Byte Data.

• Navigate to Network | System | DHCP Server, on the right side click Advanced button to get DHCP Advanced Settings window.
• Under Option Objects tab, click Add Option to get Add DHCP Option Object window.

EXAMPLE: We need to add SIP server IP 10.11.12.13 under DHCP option 120

1. Go to Network  DHCP Server and click on Advanced
2. Click on Add Option and
3. Type an "Option Name"
4. Select "120 (SIP Servers DHCP Option)" for "Option Number"
5. Select "option array"
6. Select  "One Byte Data" for "Option Type"
7. Enter the following string  1;10; 11; 12; 13 as option value

EXAMPLE: We need to multiple SIP server IPs (10.11.12.13  172.21.0.1 192.168.1.100) under DHCP option 120

1. Go to Network  DHCP Server and click on Advanced
2. Click on Add Option and
   
3. Type an "Option Name"
4. Select "120 (SIP Servers DHCP Option)" for "Option Number"
5. Select "option array"
6. Select "One Byte Data" for "Option Type"
7. Enter the following string 1; 10; 11; 12; 13; 172; 21; 0; 2; 192; 168; 1; 100 as option value (decimal value for the 3 IP addresses).

Resolution for SonicOS 6.5

This release includes significant user interface changes and many new features that are different from the SonicOS 6.2 and earlier firmware. The below resolution is for customers using SonicOS 6.5 firmware.

How to configure option 120 on SonicWall DHCP server?

For DHCP option 120:

Available option types are:

• IP Address
• Domain name
  
• Four byte data
  
• two byte data
• one byte
• data
• String
• Boolean
• Hex string

 NOTE: For DHCP Option 120 use option type One Byte Data.

• Navigate to Manage | Network | DHCP Server, on the right side click Advanced button to get DHCP Advanced Settings window.
• Under Option Objects tab, click Add Option to get Add DHCP Option Object window.

EXAMPLE: We need to add SIP server IP 10.11.12.13 under DHCP option 120

1. Go to Network  DHCP Server and click on Advanced
2. Click on Add Option and
3. Type an "Option Name"
4. Select "120 (SIP Servers DHCP Option)" for "Option Number"
5. Select "option array"
6. Select  "One Byte Data" for "Option Type"
7. Enter the following string  1;10; 11; 12; 13 as option value

EXAMPLE: We need to multiple SIP server IPs (10.11.12.13  172.21.0.1 192.168.1.100) under DHCP option 120

1. Go to Network  DHCP Server and click on Advanced
2. Click on Add Option and
   
3. Type an "Option Name"
4. Select "120 (SIP Servers DHCP Option)" for "Option Number"
5. Select "option array"
6. Select "One Byte Data" for "Option Type"
7. Enter the following string 1; 10; 11; 12; 13; 172; 21; 0; 2; 192; 168; 1; 100 as option value (decimal value for the 3 IP addresses).
   
   
   

Resolution for SonicOS 6.2 and Below

The below resolution is for customers using SonicOS 6.2 and earlier firmware. For firewalls that are generation 6 and newer we suggest to upgrade to the latest general release of SonicOS 6.5 firmware.

How to configure option 120 on SonicWall DHCP server?

For DHCP option 120:

Available option types are:

• IP Address
• Domain name
  
• Four byte data
  
• two byte data
• one byte
• data
• String
• Boolean
• Hex string

NOTE: For DHCP Option 120 use option type One Byte Data.

• Navigate to Network | DHCP Server, on the right side click Advanced button to get DHCP Advanced Settings window.
• Under Option Objects tab, click Add Option to get Add DHCP Option Object window.

EXAMPLE: We need to add SIP server IP 10.11.12.13 under DHCP option 120

1. Go to Network  DHCP Server and click on Advanced
2. Click on Add Option and
3. Type an "Option Name"
4. Select "120 (SIP Servers DHCP Option)" for "Option Number"
5. Select "option array"
6. Select  "One Byte Data" for "Option Type"
7. Enter the following string  1;10; 11; 12; 13 as option value

EXAMPLE: We need to multiple SIP server IPs (10.11.12.13  172.21.0.1 192.168.1.100) under DHCP option 120

1. Go to Network  DHCP Server and click on Advanced
2. Click on Add Option and
   
3. Type an "Option Name"
4. Select "120 (SIP Servers DHCP Option)" for "Option Number"
5. Select "option array"
6. Select "One Byte Data" for "Option Type"
7. Enter the following string 1; 10; 11; 12; 13; 172; 21; 0; 2; 192; 168; 1; 100 as option value (decimal value for the 3 IP addresses).