diff --git a/compos/composd/src/instance_starter.rs b/compos/composd/src/instance_starter.rs
index ec95ff8..1751d35 100644
--- a/compos/composd/src/instance_starter.rs
+++ b/compos/composd/src/instance_starter.rs
@@ -89,8 +89,8 @@
         let key_blob = fs::read(&self.key_blob).context("Reading private key blob")?;
         let public_key = fs::read(&self.public_key).context("Reading public key")?;
 
-        let vm_instance = VmInstance::start(&self.instance_image).context("Starting VM")?;
-        let service = vm_instance.get_service().context("Connecting to CompOS")?;
+        let compos_instance = self.start_vm()?;
+        let service = &compos_instance.service;
 
         if !service.verifySigningKey(&key_blob, &public_key).context("Verifying key pair")? {
             bail!("Key pair invalid");
@@ -102,7 +102,7 @@
 
         service.initializeSigningKey(&key_blob).context("Loading signing key")?;
 
-        Ok(CompOsInstance { vm_instance, service })
+        Ok(compos_instance)
     }
 
     fn start_new_instance(
@@ -116,8 +116,8 @@
 
         self.create_instance_image(virtualization_service)?;
 
-        let vm_instance = VmInstance::start(&self.instance_image).context("Starting VM")?;
-        let service = vm_instance.get_service().context("Connecting to CompOS")?;
+        let compos_instance = self.start_vm()?;
+        let service = &compos_instance.service;
 
         let key_data = service.generateSigningKey().context("Generating signing key")?;
         fs::write(&self.key_blob, &key_data.keyBlob).context("Writing key blob")?;
@@ -133,6 +133,17 @@
 
         service.initializeSigningKey(&key_data.keyBlob).context("Loading signing key")?;
 
+        Ok(compos_instance)
+    }
+
+    fn start_vm(&self) -> Result<CompOsInstance> {
+        let instance_image = fs::OpenOptions::new()
+            .read(true)
+            .write(true)
+            .open(&self.instance_image)
+            .context("Failed to open instance image")?;
+        let vm_instance = VmInstance::start(instance_image).context("Starting VM")?;
+        let service = vm_instance.get_service().context("Connecting to CompOS")?;
         Ok(CompOsInstance { vm_instance, service })
     }