Merge pull request #104456 from endgame/refresh-instance-metadata-on-boot

Refresh instance metadata on boot

2 files changed, 25 insertions, 29 deletions

diff --git a/nixos/modules/virtualisation/ec2-metadata-fetcher.nix b/nixos/modules/virtualisation/ec2-metadata-fetcher.nix
index 812e93ec4aabb..dca5c2abd4e0c 100644
--- a/nixos/modules/virtualisation/ec2-metadata-fetcher.nix
+++ b/nixos/modules/virtualisation/ec2-metadata-fetcher.nix
@@ -8,9 +8,14 @@
 # Make sure that every package you depend on here is already listed as
 # a channel blocker for both the full-sized and small channels.
 # Otherwise, we risk breaking user deploys in released channels.
+#
+# Also note: OpenStack's metadata service for its instances aims to be
+# compatible with the EC2 IMDS. Where possible, try to keep the set of
+# fetched metadata in sync with ./openstack-metadata-fetcher.nix .
 ''
   metaDir=${targetRoot}etc/ec2-metadata
   mkdir -m 0755 -p "$metaDir"
+  rm -f "$metaDir/*"
 
   get_imds_token() {
     # retry-delay of 1 selected to give the system a second to get going,
@@ -61,19 +66,12 @@
 
   echo "getting EC2 instance metadata..."
 
-  if ! [ -e "$metaDir/ami-manifest-path" ]; then
-    wget ${wgetExtraOptions} --header "X-aws-ec2-metadata-token: $IMDS_TOKEN" -O "$metaDir/ami-manifest-path" http://169.254.169.254/1.0/meta-data/ami-manifest-path
-  fi
-
-  if ! [ -e "$metaDir/user-data" ]; then
-    wget ${wgetExtraOptions} --header "X-aws-ec2-metadata-token: $IMDS_TOKEN" -O "$metaDir/user-data" http://169.254.169.254/1.0/user-data && chmod 600 "$metaDir/user-data"
-  fi
-
-  if ! [ -e "$metaDir/hostname" ]; then
-    wget ${wgetExtraOptions} --header "X-aws-ec2-metadata-token: $IMDS_TOKEN" -O "$metaDir/hostname" http://169.254.169.254/1.0/meta-data/hostname
-  fi
+  wget_imds() {
+    wget ${wgetExtraOptions} --header "X-aws-ec2-metadata-token: $IMDS_TOKEN" "$@";
+  }
 
-  if ! [ -e "$metaDir/public-keys-0-openssh-key" ]; then
-    wget ${wgetExtraOptions} --header "X-aws-ec2-metadata-token: $IMDS_TOKEN" -O "$metaDir/public-keys-0-openssh-key" http://169.254.169.254/1.0/meta-data/public-keys/0/openssh-key
-  fi
+  wget_imds -O "$metaDir/ami-manifest-path" http://169.254.169.254/1.0/meta-data/ami-manifest-path
+  wget_imds -O "$metaDir/user-data" http://169.254.169.254/1.0/user-data && chmod 600 "$metaDir/user-data"
+  wget_imds -O "$metaDir/hostname" http://169.254.169.254/1.0/meta-data/hostname
+  wget_imds -O "$metaDir/public-keys-0-openssh-key" http://169.254.169.254/1.0/meta-data/public-keys/0/openssh-key
 ''
diff --git a/nixos/modules/virtualisation/openstack-metadata-fetcher.nix b/nixos/modules/virtualisation/openstack-metadata-fetcher.nix
index b531787c31a29..8c191397cf9a5 100644
--- a/nixos/modules/virtualisation/openstack-metadata-fetcher.nix
+++ b/nixos/modules/virtualisation/openstack-metadata-fetcher.nix
@@ -1,23 +1,21 @@
 { targetRoot, wgetExtraOptions }:
+
+# OpenStack's metadata service aims to be EC2-compatible. Where
+# possible, try to keep the set of fetched metadata in sync with
+# ./ec2-metadata-fetcher.nix .
 ''
   metaDir=${targetRoot}etc/ec2-metadata
   mkdir -m 0755 -p "$metaDir"
+  rm -f "$metaDir/*"
 
-  echo "getting EC2 instance metadata..."
-
-  if ! [ -e "$metaDir/ami-manifest-path" ]; then
-    wget ${wgetExtraOptions} -O "$metaDir/ami-manifest-path" http://169.254.169.254/1.0/meta-data/ami-manifest-path
-  fi
-
-  if ! [ -e "$metaDir/user-data" ]; then
-    wget ${wgetExtraOptions} -O "$metaDir/user-data" http://169.254.169.254/1.0/user-data && chmod 600 "$metaDir/user-data"
-  fi
+  echo "getting instance metadata..."
 
-  if ! [ -e "$metaDir/hostname" ]; then
-    wget ${wgetExtraOptions} -O "$metaDir/hostname" http://169.254.169.254/1.0/meta-data/hostname
-  fi
+  wget_imds() {
+    wget ${wgetExtraOptions} "$@"
+  }
 
-  if ! [ -e "$metaDir/public-keys-0-openssh-key" ]; then
-    wget ${wgetExtraOptions} -O "$metaDir/public-keys-0-openssh-key" http://169.254.169.254/1.0/meta-data/public-keys/0/openssh-key
-  fi
+  wget_imds -O "$metaDir/ami-manifest-path" http://169.254.169.254/1.0/meta-data/ami-manifest-path
+  wget_imds -O "$metaDir/user-data" http://169.254.169.254/1.0/user-data && chmod 600 "$metaDir/user-data"
+  wget_imds -O "$metaDir/hostname" http://169.254.169.254/1.0/meta-data/hostname
+  wget_imds -O "$metaDir/public-keys-0-openssh-key" http://169.254.169.254/1.0/meta-data/public-keys/0/openssh-key
 ''