diff --git a/.devcontainer/init-firewall.sh b/.devcontainer/init-firewall.sh
index 16d492dd26..1215fc5782 100644
--- a/.devcontainer/init-firewall.sh
+++ b/.devcontainer/init-firewall.sh
@@ -74,7 +74,7 @@ for domain in \
     "vscode.blob.core.windows.net" \
     "update.code.visualstudio.com"; do
     echo "Resolving $domain..."
-    ips=$(dig +noall +answer A "$domain" | awk '$4 == "A" {print $5}')
+    ips=$(dig +noall +answer A "$domain" | awk '$4 == "A" {print $5}' | sort -u)
     if [ -z "$ips" ]; then
         echo "ERROR: Failed to resolve $domain"
         exit 1