From f05bf31083d07b282d97ba6e8f4c40860e2a3638 Mon Sep 17 00:00:00 2001
From: hwdsl2 <hwdsl2@users.noreply.github.com>
Date: Sun, 20 Nov 2022 15:05:02 -0600
Subject: [PATCH] Improve sysctl settings

- For enabling TCP BBR congestion control, add a check to make sure
  tcp_congestion_control exists.
---
 openvpn-install.sh | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/openvpn-install.sh b/openvpn-install.sh
index b1dbd62..7ca2a4e 100644
--- a/openvpn-install.sh
+++ b/openvpn-install.sh
@@ -424,7 +424,8 @@ update_sysctl() {
 		|| { /bin/rm -f "$conf_opt"; touch "$conf_opt"; }
 	# Enable TCP BBR congestion control if kernel version >= 4.20
 	if modprobe -q tcp_bbr \
-		&& printf '%s\n%s' "4.20" "$(uname -r)" | sort -C -V; then
+		&& printf '%s\n%s' "4.20" "$(uname -r)" | sort -C -V \
+		&& [ -f /proc/sys/net/ipv4/tcp_congestion_control ]; then
 cat >> "$conf_opt" <<'EOF'
 net.core.default_qdisc = fq
 net.ipv4.tcp_congestion_control = bbr