From 797f81249548d8ff6a65c15d3272a5e9dd270bcc Mon Sep 17 00:00:00 2001
From: Narthana Epa <narthana.epa@gmail.com>
Date: Fri, 1 Sep 2023 15:51:36 +1000
Subject: [PATCH 1/3] Better error messages for mounting instance storage

---
 packer/linux/conf/bin/bk-mount-instance-storage.sh | 7 ++++---
 1 file changed, 4 insertions(+), 3 deletions(-)

diff --git a/packer/linux/conf/bin/bk-mount-instance-storage.sh b/packer/linux/conf/bin/bk-mount-instance-storage.sh
index 3d90f3b22..6f48b9ab8 100755
--- a/packer/linux/conf/bin/bk-mount-instance-storage.sh
+++ b/packer/linux/conf/bin/bk-mount-instance-storage.sh
@@ -9,15 +9,16 @@ exec > >(tee -a /var/log/elastic-stack.log | logger -t user-data -s 2>/dev/conso
 # https://docs.aws.amazon.com/AWSEC2/latest/UserGuide/InstanceStorage.html
 
 if [[ "${BUILDKITE_ENABLE_INSTANCE_STORAGE:-false}" != "true" ]]; then
-  echo "Skipping mounting instance storage"
+  echo Skipping mounting instance storage >&2
   exit 0
 fi
 
 #shellcheck disable=SC2207
 devices=($(nvme list | grep "Amazon EC2 NVMe Instance Storage" | cut -f1 -d' '))
 
-if [ -z "${devices[*]}" ]; then
-  echo "No Instance Storage NVMe drives to mount" >&2
+if [[ -z "${devices[*]}" ]]; then
+  echo No NVMe drives to mount. >&2
+  echo Please check that your instance type supports instance storage >&2
   exit 0
 fi
 

From 614cc4980e137b73969e28f29d16afe4d55989e8 Mon Sep 17 00:00:00 2001
From: Narthana Epa <narthana.epa@gmail.com>
Date: Fri, 1 Sep 2023 15:51:53 +1000
Subject: [PATCH 2/3] Don't fail when instance storage not available

---
 packer/linux/conf/bin/bk-mount-instance-storage.sh | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/packer/linux/conf/bin/bk-mount-instance-storage.sh b/packer/linux/conf/bin/bk-mount-instance-storage.sh
index 6f48b9ab8..350c61249 100755
--- a/packer/linux/conf/bin/bk-mount-instance-storage.sh
+++ b/packer/linux/conf/bin/bk-mount-instance-storage.sh
@@ -14,7 +14,7 @@ if [[ "${BUILDKITE_ENABLE_INSTANCE_STORAGE:-false}" != "true" ]]; then
 fi
 
 #shellcheck disable=SC2207
-devices=($(nvme list | grep "Amazon EC2 NVMe Instance Storage" | cut -f1 -d' '))
+devices=($(nvme list | grep "Amazon EC2 NVMe Instance Storage" | cut -f1 -d' ' || true))
 
 if [[ -z "${devices[*]}" ]]; then
   echo No NVMe drives to mount. >&2

From dd349aca8364a4c5351c23061aa8f4fb644d746f Mon Sep 17 00:00:00 2001
From: Narthana Epa <narthana.epa@gmail.com>
Date: Mon, 4 Sep 2023 16:57:27 +1000
Subject: [PATCH 3/3] Update description of EnableInstanceStorage parameter

We should tell the user to make sure that the instance type they are
using has instance storage.
---
 templates/aws-stack.yml | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/templates/aws-stack.yml b/templates/aws-stack.yml
index 7dd3ca90d..190eeb442 100644
--- a/templates/aws-stack.yml
+++ b/templates/aws-stack.yml
@@ -480,7 +480,10 @@ Parameters:
 
   EnableInstanceStorage:
     Type: String
-    Description: Mount available NVMe Instance Storage at /mnt/ephemeral
+    Description: >
+      Mount available NVMe Instance Storage at /mnt/ephemeral, and use it to store docker images and
+      containers, and the build working directory. You must ensure that the instance types have
+      instance storage available for this to have any effect. See https://docs.aws.amazon.com/AWSEC2/latest/UserGuide/instance-store-volumes.html
     AllowedValues:
       - "true"
       - "false"