diff --git a/agent_nodes.tf b/agent_nodes.tf
index 8e248e9..805f8f5 100644
--- a/agent_nodes.tf
+++ b/agent_nodes.tf
@@ -113,7 +113,7 @@ resource "null_resource" "agents_install" {
   // Install k3s
   provisioner "remote-exec" {
     inline = [
-      "INSTALL_K3S_SELINUX_WARN=${var.k3s_selinux_warn} INSTALL_K3S_VERSION=${local.k3s_version} sh /tmp/k3s-installer agent ${local.agents_metadata[each.key].flags}",
+      "${local.install_env_vars} INSTALL_K3S_VERSION=${local.k3s_version} sh /tmp/k3s-installer agent ${local.agents_metadata[each.key].flags}",
       "until systemctl is-active --quiet k3s-agent.service; do sleep 1; done"
     ]
   }
diff --git a/server_nodes.tf b/server_nodes.tf
index 73fe6d2..f02b40d 100644
--- a/server_nodes.tf
+++ b/server_nodes.tf
@@ -8,6 +8,8 @@ locals {
   // If root_advertise_ip is IPv6 wrap it in square brackets for IPv6 K3S URLs otherwise leave it raw
   root_advertise_ip_k3s = can(regex("::", local.root_advertise_ip)) ? "[${local.root_advertise_ip}]" : local.root_advertise_ip
 
+  // string representation of all specified extra k3s installation env vars
+  install_env_vars = join(" ", [for k, v in var.k3s_install_env_vars : "${k}=${v}"])
 
   root_server_connection = {
     type = try(var.servers[local.root_server_name].connection.type, "ssh")
@@ -213,7 +215,7 @@ resource "null_resource" "servers_install" {
   // Install k3s server
   provisioner "remote-exec" {
     inline = [
-      "INSTALL_K3S_SELINUX_WARN=${var.k3s_selinux_warn} INSTALL_K3S_VERSION=${local.k3s_version} sh /tmp/k3s-installer server ${local.servers_metadata[each.key].flags}",
+      "${local.install_env_vars} INSTALL_K3S_VERSION=${local.k3s_version} sh /tmp/k3s-installer server ${local.servers_metadata[each.key].flags}",
       "until ${local.kubectl_cmd} get node ${local.servers_metadata[each.key].name}; do sleep 1; done"
     ]
   }
diff --git a/terraform.tfvars b/terraform.tfvars
new file mode 100644
index 0000000..77b6fb2
--- /dev/null
+++ b/terraform.tfvars
@@ -0,0 +1,3 @@
+k3s_install_env_vars = {
+  INSTALL_K3S_BIN_DIR = "/usr/bin"
+}
\ No newline at end of file
diff --git a/variables.tf b/variables.tf
index fa6eb57..927bed3 100644
--- a/variables.tf
+++ b/variables.tf
@@ -9,10 +9,15 @@ variable "k3s_version" {
   default     = "latest"
 }
 
-variable "k3s_selinux_warn" {
-  description = "Force the install script to log a warning rather than fail when k3s tries to install the SELinux policies."
-  type        = bool
-  default     = false
+variable "k3s_install_env_vars" {
+  description = "map of enviroment variables that are passed to the k3s installation script (see https://docs.k3s.io/reference/env-variables)"
+  type        = map(string)
+  default     = null
+
+  validation {
+    condition     = !can(var.k3s_install_env_vars["INSTALL_K3S_VERSION"])
+    error_message = "env var \"INSTALL_K3S_VERSION\" needs to be set via variable k3s_version"
+  }
 }
 
 variable "name" {
@@ -95,7 +100,7 @@ variable "servers" {
   }
   validation {
     condition     = !can(values(var.servers)[*].flags) || !contains([for v in var.servers : can(tolist(v.flags))], false)
-    error_message = "Field servers.<name>.flags must be a list of string."
+    error_message = "Field servers.<name>.flags must be a list of string (see: https://docs.k3s.io/cli/server)."
   }
   validation {
     condition     = !can(values(var.servers)[*].annotations) || !contains([for v in var.servers : can(tomap(v.annotations))], false)
@@ -126,7 +131,7 @@ variable "agents" {
   }
   validation {
     condition     = !can(values(var.agents)[*].flags) || !contains([for v in var.agents : can(tolist(v.flags))], false)
-    error_message = "Field agents.<name>.flags must be a list of string."
+    error_message = "Field agents.<name>.flags must be a list of string (see: https://docs.k3s.io/cli/agent)."
   }
   validation {
     condition     = !can(values(var.agents)[*].annotations) || !contains([for v in var.agents : can(tomap(v.annotations))], false)