Routing

Hi All,

When we display the LSDB using "show ospf database" command its listing the options field.

I am aware what info is carried in options filed. But not able to relate it with the LSA.

What does the values 0X20, 0X22, 0X28 imply? And what all are the options that can be present?

Regards,

Pavan

Check out section A.2 of the OSPF RFC 2328:

https://tools.ietf.org/rfc/rfc2328.txt

Hi,

I have referred to thi earlier. These are the fileds in options


  +------------------------------------+
                       | * | * | DC | EA | N/P | MC | E | * |
                       +------------------------------------

 But i wanted to correlate the values. 0X20, 0X22, 0X28 etc;

Hello,

The diagram You posted is not the latest one

                +--------------------------------------+
                | DN | O | DC | EA | N/P | MC | E | MT |
                +--------------------------------------+

                             The Options Field

https://tools.ietf.org/html/rfc5250#appendix-A.1 

Now, you have to convert Your examples into binary

0x20 would be 0010 0000 => Bit DC is set, all other bits are cleared 

0x22 would be 0010 0010 => Bits DC is set, bit E is set, all other bits are cleared

0x28 would be 0010 1000 => Bit DC is set, bit N/P is set, all other bits are cleared

HTH

Thanks

Alex