diff --git a/app/controllers/admin/ip_blocks_controller.rb b/app/controllers/admin/ip_blocks_controller.rb
index a87520f4ed25874af0e0501c494ea819170a3ff8..1bd7ec8059672c5b55c3445488b05662c1d932f0 100644
--- a/app/controllers/admin/ip_blocks_controller.rb
+++ b/app/controllers/admin/ip_blocks_controller.rb
@@ -5,7 +5,7 @@ module Admin
     def index
       authorize :ip_block, :index?
 
-      @ip_blocks = IpBlock.page(params[:page])
+      @ip_blocks = IpBlock.order(ip: :asc).page(params[:page])
       @form      = Form::IpBlockBatch.new
     end
 
diff --git a/app/models/ip_block.rb b/app/models/ip_block.rb
index 8666f4248e1aed470adcd41222296a3f2ed97daf..31343f0e114dfc0f8d63330bd60efce0090cca24 100644
--- a/app/models/ip_block.rb
+++ b/app/models/ip_block.rb
@@ -25,6 +25,7 @@ class IpBlock < ApplicationRecord
   }
 
   validates :ip, :severity, presence: true
+  validates :ip, uniqueness: true
 
   after_commit :reset_cache
 
diff --git a/db/migrate/20221025171544_add_index_ip_blocks_on_ip.rb b/db/migrate/20221025171544_add_index_ip_blocks_on_ip.rb
new file mode 100644
index 0000000000000000000000000000000000000000..0221369b7e6d659a2b90e3ac8e887acb8c1e1984
--- /dev/null
+++ b/db/migrate/20221025171544_add_index_ip_blocks_on_ip.rb
@@ -0,0 +1,17 @@
+class AddIndexIpBlocksOnIp < ActiveRecord::Migration[6.1]
+  disable_ddl_transaction!
+
+  def up
+    duplicates = IpBlock.connection.select_all('SELECT string_agg(id::text, \',\') AS ids FROM ip_blocks GROUP BY ip HAVING count(*) > 1').to_ary
+
+    duplicates.each do |row|
+      IpBlock.where(id: row['ids'].split(',')[0...-1]).destroy_all
+    end
+
+    add_index :ip_blocks, :ip, unique: true, algorithm: :concurrently
+  end
+
+  def down
+    remove_index :ip_blocks, :ip, unique: true
+  end
+end
diff --git a/db/schema.rb b/db/schema.rb
index ed00d9e7427720b88fea302659d424fb003e2513..d7e40b133d0cc1bfab65a80b93d1ba151761ca7e 100644
--- a/db/schema.rb
+++ b/db/schema.rb
@@ -10,7 +10,7 @@
 #
 # It's strongly recommended that you check this file into your version control system.
 
-ActiveRecord::Schema.define(version: 2022_10_21_055441) do
+ActiveRecord::Schema.define(version: 2022_10_25_171544) do
 
   # These are extensions that must be enabled in order to support this database
   enable_extension "plpgsql"
@@ -521,6 +521,7 @@ ActiveRecord::Schema.define(version: 2022_10_21_055441) do
     t.inet "ip", default: "0.0.0.0", null: false
     t.integer "severity", default: 0, null: false
     t.text "comment", default: "", null: false
+    t.index ["ip"], name: "index_ip_blocks_on_ip", unique: true
   end
 
   create_table "list_accounts", force: :cascade do |t|