diff --git a/cloudscale/resource_cloudscale_subnet_test.go b/cloudscale/resource_cloudscale_subnet_test.go
index 7489774a..61c96094 100644
--- a/cloudscale/resource_cloudscale_subnet_test.go
+++ b/cloudscale/resource_cloudscale_subnet_test.go
@@ -535,7 +535,7 @@ func multipleSubnetConfig(rInt1 int, rInt2 int, networkIndex int, subnetIndex in
 resource "cloudscale_server" "web-worker01" {
  name = "terraform-%d"
  flavor_slug = "flex-8-4"
- image_slug = "debian-9"
+ image_slug = "%s"
  volume_size_gb = 50
  interfaces {
    type = "private"
@@ -563,5 +563,5 @@ resource "cloudscale_server" "web-worker01" {
    }`, subnetIndex, subnetIndex)
 	}
 
-	return subnetConfig_baseline(2, rInt1) + fmt.Sprintf(template, rInt2, networkTemplate, addressTemplate)
+	return subnetConfig_baseline(2, rInt1) + fmt.Sprintf(template, rInt2, DefaultImageSlug, networkTemplate, addressTemplate)
 }
diff --git a/docs/data-sources/network.md b/docs/data-sources/network.md
index a609ce59..aff446f7 100644
--- a/docs/data-sources/network.md
+++ b/docs/data-sources/network.md
@@ -20,7 +20,7 @@ resource "cloudscale_server" "gw" {
   name                = "gateway"
   zone_slug           = "lpg1"
   flavor_slug         = "flex-8-4"
-  image_slug          = "debian-9"
+  image_slug          = "debian-11"
   volume_size_gb      = 20
   ssh_keys            = ["ssh-ed25519 AAAAC3NzaC1lZDI1NTE5AAAAIL2jzgla23DfRVLQr3KT20QQYovqCCN3clHrjm2ZuQFW user@example.com"]
   interfaces {
diff --git a/docs/data-sources/server_group.md b/docs/data-sources/server_group.md
index 8f5d557f..9df91e49 100644
--- a/docs/data-sources/server_group.md
+++ b/docs/data-sources/server_group.md
@@ -18,7 +18,7 @@ resource "cloudscale_server" "web-worker01" {
   count            = 3
   name             = "web-worker${count.index}"
   flavor_slug      = "flex-8-4"
-  image_slug       = "debian-9"
+  image_slug       = "debian-11"
   server_group_ids = [data.cloudscale_server_group.web-worker-group.id]
   ssh_keys         = ["ssh-ed25519 AAAAC3NzaC1lZDI1NTE5AAAAIL2jzgla23DfRVLQr3KT20QQYovqCCN3clHrjm2ZuQFW user@example.com"]
 }
diff --git a/docs/data-sources/subnet.md b/docs/data-sources/subnet.md
index 6ba03388..ac964719 100644
--- a/docs/data-sources/subnet.md
+++ b/docs/data-sources/subnet.md
@@ -18,7 +18,7 @@ resource "cloudscale_server" "fixed" {
   name            = "fix"
   zone_slug       = "lpg1"
   flavor_slug     = "flex-4-1"
-  image_slug      = "debian-9"
+  image_slug      = "debian-11"
   interfaces      {
     type          = "public"
   }
diff --git a/docs/resources/floating_ip.md b/docs/resources/floating_ip.md
index 79075eb1..d4267ef1 100644
--- a/docs/resources/floating_ip.md
+++ b/docs/resources/floating_ip.md
@@ -13,7 +13,7 @@ Provides a cloudscale.ch Floating IP to represent a publicly-accessible static I
 resource "cloudscale_server" "web-worker01" {
   name        = "web-worker01"
   flavor_slug = "flex-8-4"
-  image_slug  = "debian-9"
+  image_slug  = "debian-11"
   ssh_keys    = ["ssh-ed25519 AAAAC3NzaC1lZDI1NTE5AAAAIL2jzgla23DfRVLQr3KT20QQYovqCCN3clHrjm2ZuQFW user@example.com"]
 }
 
diff --git a/docs/resources/network.md b/docs/resources/network.md
index 4b57c560..3085b6da 100644
--- a/docs/resources/network.md
+++ b/docs/resources/network.md
@@ -23,7 +23,7 @@ resource "cloudscale_server" "gw" {
   name                = "gateway"
   zone_slug           = "lpg1"
   flavor_slug         = "flex-8-4"
-  image_slug          = "debian-9"
+  image_slug          = "debian-11"
   volume_size_gb      = 20
   ssh_keys            = ["ssh-ed25519 AAAAC3NzaC1lZDI1NTE5AAAAIL2jzgla23DfRVLQr3KT20QQYovqCCN3clHrjm2ZuQFW user@example.com"]
   interfaces {
diff --git a/docs/resources/server.md b/docs/resources/server.md
index 9e7cfa88..cc9f6074 100644
--- a/docs/resources/server.md
+++ b/docs/resources/server.md
@@ -13,7 +13,7 @@ Provides a cloudscale.ch server resource. This can be used to create, modify, im
 resource "cloudscale_server" "web-worker01" {
   name                = "web-worker01"
   flavor_slug         = "flex-8-4"
-  image_slug          = "debian-9"
+  image_slug          = "debian-11"
   volume_size_gb      = 10
   ssh_keys            = ["ssh-ed25519 AAAAC3NzaC1lZDI1NTE5AAAAIL2jzgla23DfRVLQr3KT20QQYovqCCN3clHrjm2ZuQFW user@example.com"]
   
diff --git a/docs/resources/server_group.md b/docs/resources/server_group.md
index ac782058..c6fa7eda 100644
--- a/docs/resources/server_group.md
+++ b/docs/resources/server_group.md
@@ -20,7 +20,7 @@ resource "cloudscale_server" "web-worker01" {
   count            = 3
   name             = "web-worker${count.index}"
   flavor_slug      = "flex-8-4"
-  image_slug       = "debian-9"
+  image_slug       = "debian-11"
   server_group_ids = [cloudscale_server_group.web-worker-group.id]
   ssh_keys         = ["ssh-ed25519 AAAAC3NzaC1lZDI1NTE5AAAAIL2jzgla23DfRVLQr3KT20QQYovqCCN3clHrjm2ZuQFW user@example.com"]
 }
diff --git a/docs/resources/subnet.md b/docs/resources/subnet.md
index cda898e8..5c0a82c4 100644
--- a/docs/resources/subnet.md
+++ b/docs/resources/subnet.md
@@ -30,7 +30,7 @@ resource "cloudscale_server" "fixed" {
   name            = "fix"
   zone_slug       = "lpg1"
   flavor_slug     = "flex-4-1"
-  image_slug      = "debian-9"
+  image_slug      = "debian-11"
   interfaces      {
     type          = "public"
   }
diff --git a/docs/resources/volume.md b/docs/resources/volume.md
index 3edd72ad..30085434 100644
--- a/docs/resources/volume.md
+++ b/docs/resources/volume.md
@@ -13,7 +13,7 @@ Provides a cloudscale.ch volume (block storage) resource. This can be used to cr
 resource "cloudscale_server" "web-worker01" {
   name        = "web-worker01"
   flavor_slug = "flex-8-4"
-  image_slug  = "debian-9"
+  image_slug  = "debian-11"
   ssh_keys    = ["ssh-ed25519 AAAAC3NzaC1lZDI1NTE5AAAAIL2jzgla23DfRVLQr3KT20QQYovqCCN3clHrjm2ZuQFW user@example.com"]
 }
 
diff --git a/examples/main.tf b/examples/main.tf
index 784aa0fa..26d65e39 100644
--- a/examples/main.tf
+++ b/examples/main.tf
@@ -24,7 +24,7 @@ provider "cloudscale" {
 resource "cloudscale_server" "web-worker01" {
   name           = "web-worker01"
   flavor_slug    = "flex-8-4"
-  image_slug     = "debian-9"
+  image_slug     = "debian-11"
   volume_size_gb = 50
   ssh_keys       = ["ssh-ed25519 AAAAC3NzaC1lZDI1NTE5AAAAIL2jzgla23DfRVLQr3KT20QQYovqCCN3clHrjm2ZuQFW user@example.com"]
 }