DHCP Option 184 on Windows Server

[cyberspace]

I need to configure Option 184 to also pass out the IP address of the PSTN gateway for last resort failover.

Generally I do this on IBM System I and for the gateway parameter you enter AA (hex) as a wildcard to enter any string.

does anybody know the format for this parameter when configuring it on Windows Server?

'When all else fails.......read the manual'

 

[dgillson]

See appendix A of this doucument.

http://support.3com.com/infodeli/tools/vcx/71/vcx-7.1-installation-guide.pdf

 

[engjohn]

To create and configure the custom option 184 on a Windows 2000 Server:

1. Highlight "Action" at the top of the DHCP window

2. Select "Set Predefined Options" from the drop down menu

3. Click on the "Add" button

4. Enter the following Information in the applicable field in the window that is opened up:

a. Name: NBX NCP IP Address (any name will work this is just an example)

b. Data Type: Select "Byte" from drop down menu

cc. Check the box for "Array"

d. Code: Enter "184"

e. Click on "OK" button

5. Now you have to determine if you will be assigning this as a global option or just for specific scopes. If there are multiple NCPs that you will need to configure then Option 184 will have to be configured on a per Scope basis. If there is only one NCP then you can define it as a Global or Server option. Defining this option on subnets that do not have any NBX devices will not cause any problems. In this last case the device getting the DHCP address will just ignore that option.

6. Assigning Option 184 to an Individual Scope

a. Highlight the applicable scope

b. Click on "Scope Options"

c. Right mouse click on “Scope Options” and select “Configure Options” from the drop down menu

d. Select Option 184 by checking the box next to it. This will allow you to enter defining data as follows: You must Enter this data in the following order:

i. 1
ii. 4
iii. 1st Octet of NCP IP Address <click on "Add" button>
iv. 2nd Octet of NCP IP Address <click on "Add" button>
v. 3rd Octet of NCP IP Address <click on "Add" button>
vi. Last Octet of NCP IP Address <click on "Add" button>


7. Assigning Option 184 as a Global option which would be applied to all scopes:

a. Select Server Options under the applicable DHCP Server

b. Right mouse click on Server Options and select “Configure Options” from the drop down menu

c. Select Option 184 by checking the box next to it. This will allow you to enter defining data as follows: You must Enter this data in the following order:
i. 1
ii. 4
iii. 1st Octet of NCP IP Address <click on "Add" button>
iv. 2nd Octet of NCP IP Address <click on "Add" button>
v. 3rd Octet of NCP IP Address <click on "Add" button>
vi. Last Octet of NCP IP Address <click on "Add" button>

d. This will set it for all scopes that are configured on that DHCP Server

 

[cyberspace]

Cheers guys, I get all that stuff above - it's already running providing NCP 1&2 and VLAN information, but it's the failover gateway where the trouble is.

In testing I tried 0xAA based on my System I experience. However, this came out as 170..which is correct. However, the guide says that 0xAA in hex is the equivalent of wildcard. Is it just me or are they mistaken? Perhaps I did something else wrong?

I did notice that the guide said the type is "byte" but the live scope is actually using binary. I used byte on a test machine but still when I enter 0xAA it comes out as 170, so I presume it isn't that.

Tried the obvious and entered * but that is not valid input.

Any further advice appreciated!

'When all else fails.......read the manual'

 

[engjohn]

0x2A is hex for * I think that they may have made a typeo in the document putting 2 A's and not 2A... Try that...

 

[cyberspace]

Thanks, but 0x2A appears to be 42?

'When all else fails.......read the manual'

 

[engjohn]

0x2A is * in ASCII, 42 in Decimal, 00101010 in Binary...
0xAA is a in ASCII, 170 in Decimal, 10101010 in Binary...

 

[cyberspace]

I see - thanks. However when I add 0x2A to the DHCP option, it comes out as 42; so am I doing something wrong?

'When all else fails.......read the manual'

 

[cyberspace]

Just thought i'd give this a bump, since I can only seem to enter options in decimal or in hex formats, not binary..and could really do with getting to the bottom of it

'When all else fails.......read the manual'