From 73f21e5e260f08409ae83b87c9067c6189c1fcdb Mon Sep 17 00:00:00 2001
From: crowetic <jason@crowetic.com>
Date: Wed, 16 Apr 2025 21:02:23 +0000
Subject: [PATCH] fixed service creation, edited method of obtaining nic.

---
 vm-tool-setup.sh | 34 +++++++++++++++++++++++++---------
 1 file changed, 25 insertions(+), 9 deletions(-)

diff --git a/vm-tool-setup.sh b/vm-tool-setup.sh
index 70146bb..9d274f0 100755
--- a/vm-tool-setup.sh
+++ b/vm-tool-setup.sh
@@ -14,13 +14,33 @@ echo "=== [3/5] Trimming filesystems ==="
 sudo fstrim -av || true
 
 echo "=== [4/5] Detecting VM network interfaces ==="
-NIC_LIST=$(ls /sys/class/net | grep -Ev '^(lo|docker|br|vmbr|tap|veth)' | xargs)
+NIC_LIST=()
+for nic in /sys/class/net/*; do
+    nicname=$(basename "$nic")
+    if [[ "$nicname" != "lo" && "$nicname" != vmbr* && "$nicname" != tap* && "$nicname" != veth* && "$nicname" != docker* ]]; then
+        NIC_LIST+=("$nicname")
+    fi
+done
 
-echo "VM NICs detected: $NIC_LIST"
+if [[ ${#NIC_LIST[@]} -eq 0 ]]; then
+    echo "⚠️ No usable NICs detected. Exiting."
+    exit 1
+fi
+
+echo "VM NICs detected: ${NIC_LIST[*]}"
 
 echo "=== [5/5] Creating persistent systemd service to disable offloads ==="
 SERVICE_FILE="/etc/systemd/system/disable-vm-nic-offloads.service"
 
+DISABLE_CMDS=""
+for nic in "${NIC_LIST[@]}"; do
+    DISABLE_CMDS+="/usr/sbin/ethtool -K $nic tx off rx off tso off gso off gro off; "
+    DISABLE_CMDS+="/sbin/ip link set $nic txqueuelen 10000; "
+done
+
+# Escape for ExecStart
+DISABLE_CMDS_ESCAPED=$(printf '%q ' "$DISABLE_CMDS")
+
 sudo tee "$SERVICE_FILE" > /dev/null <<EOF
 [Unit]
 Description=Disable all VM NIC offloads at boot
@@ -28,12 +48,7 @@ After=network.target
 
 [Service]
 Type=oneshot
-ExecStart=/bin/bash -c '
-$(for nic in $NIC_LIST; do
-    echo "/usr/sbin/ethtool -K $nic tx off rx off tso off gso off gro off;"
-    echo "/sbin/ip link set $nic txqueuelen 10000;"
-done)
-'
+ExecStart=/bin/bash -c "$DISABLE_CMDS_ESCAPED"
 RemainAfterExit=yes
 
 [Install]
@@ -41,11 +56,12 @@ WantedBy=multi-user.target
 EOF
 
 echo "=== Enabling and starting NIC offload disable service ==="
+sudo systemctl daemon-reexec
 sudo systemctl daemon-reload
 sudo systemctl enable --now disable-vm-nic-offloads.service
 
 echo "=== ✅ VM NIC setup complete ==="
-for nic in $NIC_LIST; do
+for nic in "${NIC_LIST[@]}"; do
     echo "--- $nic ---"
     ethtool -k "$nic" | grep -E 'segmentation|offload|scatter|checksum'
     ip link show "$nic" | grep txqueuelen