diff --git a/kcptun/Dockerfile b/kcptun/Dockerfile
index 47aaccc..0491213 100644
--- a/kcptun/Dockerfile
+++ b/kcptun/Dockerfile
@@ -5,13 +5,14 @@
 FROM alpine:3
 MAINTAINER EasyPi Software Foundation
 
-ENV KCPTUN_VERSION=20210922
-ENV KCPTUN_FILE=kcptun-linux-amd64-${KCPTUN_VERSION}.tar.gz
-ENV KCPTUN_URL=https://github.com/xtaci/kcptun/releases/download/v${KCPTUN_VERSION}/${KCPTUN_FILE}
+ARG KCPTUN_VERSION=20230214
+ARG KCPTUN_FILE=kcptun-linux-amd64-${KCPTUN_VERSION}.tar.gz
+ARG KCPTUN_URL=https://github.com/xtaci/kcptun/releases/download/v${KCPTUN_VERSION}/${KCPTUN_FILE}
 
 RUN set -xe \
     && apk add --no-cache curl \
     && curl -sSL ${KCPTUN_URL} | tar xz -C /usr/local/bin \
+    && server_linux_amd64 --version \
     && apk del curl
 
 ENTRYPOINT ["server_linux_amd64"]
diff --git a/kcptun/systemd/kcptun.service b/kcptun/systemd/kcptun.service
index 40320f3..743146d 100644
--- a/kcptun/systemd/kcptun.service
+++ b/kcptun/systemd/kcptun.service
@@ -5,6 +5,7 @@ After=network.target
 [Service]
 EnvironmentFile=-/etc/default/kcptun
 ExecStart=/usr/bin/kcptun $KCPTUN_OPTS
+LimitNOFILE=65536
 Restart=on-failure
 
 [Install]