Custom query to fetch all entries of a table and that only contains first of many duplicates based on a specific column

I have a Location model and the table looks like

id	name	vin	ip_address	created_at	updated_at
0	default	0	0.0.0.0/0	2021-11-08 11:54:26.822623	2021-11-08 11:54:26.822623
1	admin	1	10.108.150.143	2021-11-08 11:54:26.82885	2021-11-08 11:54:26.82885
2	V122	122	10.108.150.122	2021-11-08 11:54:26.82885	2021-11-08 11:54:26.82885
3	V123	123	10.108.150.123	2021-11-08 11:54:26.82885	2021-11-08 11:54:26.82885
4	V124	124	10.108.150.124	2021-11-08 11:54:26.82885	2021-11-08 11:54:26.82885
5	V122	122	10.108.150.122	2021-11-08 11:54:26.82885	2021-11-08 11:54:26.82885
6	V125	122	10.108.150.125	2021-11-08 11:54:26.82885	2021-11-08 11:54:26.82885

My method in the Location model

   def self.find_all_non_duplicate
     return self.find(:all, :conditions => "id <> 1")
   end

I want to fetch all entries of the locations table except the entry with id = 1 and that contains only the first entry of many duplicates based on the column ip_address.

Since ip_address of id = 2 and id = 5 is duplicate. I want to keep the first entry of many duplicates i.e., id = 2.

The expected result is

id	name	vin	ip_address	created_at	updated_at
0	default	0	0.0.0.0/0	2021-11-08 11:54:26.822623	2021-11-08 11:54:26.822623
2	V122	122	10.108.150.122	2021-11-08 11:54:26.82885	2021-11-08 11:54:26.82885
3	V123	123	10.108.150.123	2021-11-08 11:54:26.82885	2021-11-08 11:54:26.82885
4	V124	124	10.108.150.124	2021-11-08 11:54:26.82885	2021-11-08 11:54:26.82885
6	V125	122	10.108.150.125	2021-11-08 11:54:26.82885	2021-11-08 11:54:26.82885

The entries with id's 1 and 5 to be ignored

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