diff --git a/Gemfile b/Gemfile
index 615a1d959f..75cbddfd77 100644
--- a/Gemfile
+++ b/Gemfile
@@ -162,7 +162,5 @@ if ENV["ORACLE_ENHANCED"]
   gem "activerecord-oracle_enhanced-adapter", github: "rsim/oracle-enhanced", branch: "master"
 end
 
-# A gem necessary for Active Record tests with IBM DB.
-gem "ibm_db" if ENV["IBM_DB"]
 gem "tzinfo-data", platforms: [:mingw, :mswin, :x64_mingw, :jruby]
 gem "wdm", ">= 0.1.0", platforms: [:mingw, :mswin, :x64_mingw, :mswin64]
diff --git a/activerecord/Rakefile b/activerecord/Rakefile
index 06138680ee..0704b933d5 100644
--- a/activerecord/Rakefile
+++ b/activerecord/Rakefile
@@ -47,10 +47,10 @@ namespace :db do
   task drop: ["db:mysql:drop", "db:postgresql:drop"]
 end
 
-%w( mysql2 postgresql sqlite3 sqlite3_mem db2 oracle jdbcmysql jdbcpostgresql jdbcsqlite3 jdbcderby jdbch2 jdbchsqldb ).each do |adapter|
+%w( mysql2 postgresql sqlite3 sqlite3_mem oracle jdbcmysql jdbcpostgresql jdbcsqlite3 jdbcderby jdbch2 jdbchsqldb ).each do |adapter|
   namespace :test do
     Rake::TestTask.new(adapter => "#{adapter}:env") { |t|
-      adapter_short = adapter == "db2" ? adapter : adapter[/^[a-z0-9]+/]
+      adapter_short = adapter[/^[a-z0-9]+/]
       t.libs << "test"
       t.test_files = (FileList["test/cases/**/*_test.rb"].reject {
         |x| x.include?("/adapters/")
@@ -63,7 +63,7 @@ end
 
     namespace :isolated do
       task adapter => "#{adapter}:env" do
-        adapter_short = adapter == "db2" ? adapter : adapter[/^[a-z0-9]+/]
+        adapter_short = adapter[/^[a-z0-9]+/]
         puts [adapter, adapter_short].inspect
 
         dash_i = [
diff --git a/activerecord/test/config.example.yml b/activerecord/test/config.example.yml
index f5e3ac3c19..79b7dacbd6 100644
--- a/activerecord/test/config.example.yml
+++ b/activerecord/test/config.example.yml
@@ -35,20 +35,6 @@ connections:
       database: <%= FIXTURES_ROOT %>/fixture_database_2.sqlite3
       timeout:  5000
 
-  db2:
-    arunit:
-      adapter:  ibm_db
-      host:     localhost
-      username: arunit
-      password: arunit
-      database: arunit
-    arunit2:
-      adapter:  ibm_db
-      host:     localhost
-      username: arunit
-      password: arunit
-      database: arunit2
-
   mysql2:
     arunit:
       username: rails
diff --git a/railties/lib/rails/generators/database.rb b/railties/lib/rails/generators/database.rb
index 461716efd0..6aa6404323 100644
--- a/railties/lib/rails/generators/database.rb
+++ b/railties/lib/rails/generators/database.rb
@@ -4,7 +4,7 @@ module Rails
   module Generators
     module Database # :nodoc:
       JDBC_DATABASES = %w( jdbcmysql jdbcsqlite3 jdbcpostgresql jdbc )
-      DATABASES = %w( mysql postgresql sqlite3 oracle frontbase ibm_db sqlserver ) + JDBC_DATABASES
+      DATABASES = %w( mysql postgresql sqlite3 oracle sqlserver ) + JDBC_DATABASES
 
       def initialize(*)
         super
@@ -17,7 +17,6 @@ module Rails
         when "postgresql"     then ["pg", [">= 0.18", "< 2.0"]]
         when "sqlite3"        then ["sqlite3", ["~> 1.4"]]
         when "oracle"         then ["activerecord-oracle_enhanced-adapter", nil]
-        when "frontbase"      then ["ruby-frontbase", nil]
         when "sqlserver"      then ["activerecord-sqlserver-adapter", nil]
         when "jdbcmysql"      then ["activerecord-jdbcmysql-adapter", nil]
         when "jdbcsqlite3"    then ["activerecord-jdbcsqlite3-adapter", nil]
diff --git a/railties/lib/rails/generators/rails/app/templates/config/databases/frontbase.yml.tt b/railties/lib/rails/generators/rails/app/templates/config/databases/frontbase.yml.tt
deleted file mode 100644
index 53724f32b6..0000000000
--- a/railties/lib/rails/generators/rails/app/templates/config/databases/frontbase.yml.tt
+++ /dev/null
@@ -1,51 +0,0 @@
-# FrontBase versions 4.x
-#
-# Get the bindings:
-#   gem install ruby-frontbase
-#
-# Configure Using Gemfile
-# gem 'ruby-frontbase'
-#
-default: &default
-  adapter: frontbase
-  pool: <%%= ENV.fetch("RAILS_MAX_THREADS") { 5 } %>
-  host: localhost
-  username: <%= app_name %>
-  password: ''
-
-development:
-  <<: *default
-  database: <%= app_name %>_development
-
-# Warning: The database defined as "test" will be erased and
-# re-generated from your development database when you run "rake".
-# Do not set this db to the same as development or production.
-test:
-  <<: *default
-  database: <%= app_name %>_test
-
-# As with config/credentials.yml, you never want to store sensitive information,
-# like your database password, in your source code. If your source code is
-# ever seen by anyone, they now have access to your database.
-#
-# Instead, provide the password or a full connection URL as an environment
-# variable when you boot the app. For example:
-#
-#   DATABASE_URL="frontbase://myuser:mypass@localhost/somedatabase"
-#
-# If the connection URL is provided in the special DATABASE_URL environment
-# variable, Rails will automatically merge its configuration values on top of
-# the values provided in this file. Alternatively, you can specify a connection
-# URL environment variable explicitly:
-#
-#   production:
-#     url: <%%= ENV['MY_APP_DATABASE_URL'] %>
-#
-# Read https://guides.rubyonrails.org/configuring.html#configuring-a-database
-# for a full overview on how database connection configuration can be specified.
-#
-production:
-  <<: *default
-  database: <%= app_name %>_production
-  username: <%= app_name %>
-  password: <%%= ENV['<%= app_name.upcase %>_DATABASE_PASSWORD'] %>
diff --git a/railties/lib/rails/generators/rails/app/templates/config/databases/ibm_db.yml.tt b/railties/lib/rails/generators/rails/app/templates/config/databases/ibm_db.yml.tt
deleted file mode 100644
index 67a7701ab8..0000000000
--- a/railties/lib/rails/generators/rails/app/templates/config/databases/ibm_db.yml.tt
+++ /dev/null
@@ -1,87 +0,0 @@
-# IBM Dataservers
-#
-# Home Page
-#   https://github.com/dparnell/ibm_db
-#
-# To install the ibm_db gem:
-#
-#   On Linux:
-#       . /home/db2inst1/sqllib/db2profile
-#       export IBM_DB_INCLUDE=/opt/ibm/db2/V9.7/include
-#       export IBM_DB_LIB=/opt/ibm/db2/V9.7/lib32
-#       gem install ibm_db
-#
-#   On Mac OS X 10.5:
-#       . /home/db2inst1/sqllib/db2profile
-#       export IBM_DB_INCLUDE=/opt/ibm/db2/V9.7/include
-#       export IBM_DB_LIB=/opt/ibm/db2/V9.7/lib32
-#       export ARCHFLAGS="-arch i386"
-#       gem install ibm_db
-#
-#   On Mac OS X 10.6:
-#       . /home/db2inst1/sqllib/db2profile
-#       export IBM_DB_INCLUDE=/opt/ibm/db2/V9.7/include
-#       export IBM_DB_LIB=/opt/ibm/db2/V9.7/lib64
-#       export ARCHFLAGS="-arch x86_64"
-#       gem install ibm_db
-#
-#   On Windows:
-#       Issue the command: gem install ibm_db
-#
-# Configure Using Gemfile
-# gem 'ibm_db'
-#
-#
-default: &default
-  adapter: ibm_db
-  pool: <%%= ENV.fetch("RAILS_MAX_THREADS") { 5 } %>
-  username: db2inst1
-  password:
-  #schema: db2inst1
-  #host: localhost
-  #port: 50000
-  #account: my_account
-  #app_user: my_app_user
-  #application: my_application
-  #workstation: my_workstation
-  #security: SSL
-  #timeout: 10
-  #authentication: SERVER
-  #parameterized: false
-
-development:
-  <<: *default
-  database: <%= app_name[0,4] %>_dev
-
-# Warning: The database defined as "test" will be erased and
-# re-generated from your development database when you run "rake".
-# Do not set this db to the same as development or production.
-test:
-  <<: *default
-  database: <%= app_name[0,4] %>_tst
-
-# As with config/credentials.yml, you never want to store sensitive information,
-# like your database password, in your source code. If your source code is
-# ever seen by anyone, they now have access to your database.
-#
-# Instead, provide the password or a full connection URL as an environment
-# variable when you boot the app. For example:
-#
-#   DATABASE_URL="ibm-db://myuser:mypass@localhost/somedatabase"
-#
-# If the connection URL is provided in the special DATABASE_URL environment
-# variable, Rails will automatically merge its configuration values on top of
-# the values provided in this file. Alternatively, you can specify a connection
-# URL environment variable explicitly:
-#
-#   production:
-#     url: <%%= ENV['MY_APP_DATABASE_URL'] %>
-#
-# Read https://guides.rubyonrails.org/configuring.html#configuring-a-database
-# for a full overview on how database connection configuration can be specified.
-#
-production:
-  <<: *default
-  database: <%= app_name %>_production
-  username: <%= app_name %>
-  password: <%%= ENV['<%= app_name.upcase %>_DATABASE_PASSWORD'] %>
diff --git a/railties/test/commands/db_system_change_test.rb b/railties/test/commands/db_system_change_test.rb
index 2ff45a7878..374a9ce69f 100644
--- a/railties/test/commands/db_system_change_test.rb
+++ b/railties/test/commands/db_system_change_test.rb
@@ -26,8 +26,8 @@ class Rails::Command::Db::System::ChangeCommandTest < ActiveSupport::TestCase
     assert_match <<~MSG.squish, output
       Invalid value for --to option.
       Supported preconfigurations are:
-      mysql, postgresql, sqlite3, oracle, frontbase,
-      ibm_db, sqlserver, jdbcmysql, jdbcsqlite3,
+      mysql, postgresql, sqlite3, oracle,
+      sqlserver, jdbcmysql, jdbcsqlite3,
       jdbcpostgresql, jdbc.
     MSG
   end
diff --git a/railties/test/generators/db_system_change_generator_test.rb b/railties/test/generators/db_system_change_generator_test.rb
index 6afe01ad3b..7597fe935a 100644
--- a/railties/test/generators/db_system_change_generator_test.rb
+++ b/railties/test/generators/db_system_change_generator_test.rb
@@ -24,8 +24,8 @@ module Rails
             assert_match <<~MSG.squish, output
               Invalid value for --to option.
               Supported preconfigurations are:
-              mysql, postgresql, sqlite3, oracle, frontbase,
-              ibm_db, sqlserver, jdbcmysql, jdbcsqlite3,
+              mysql, postgresql, sqlite3, oracle,
+              sqlserver, jdbcmysql, jdbcsqlite3,
               jdbcpostgresql, jdbc.
             MSG
           end