diff --git a/CHANGELOG.md b/CHANGELOG.md
index 395d7f1..ebef5b9 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -6,9 +6,15 @@ Summary of release changes for Version 2.
 
 CentOS-7 7.5.1804 x86_64 - Memcached 1.4.
 
+### 2.1.1 - 2018-11-16
+
+- Fixes typo in test; using `--format` instead of `--filter`.
+- Adds required `--sysctl` settings to docker run templates.
+- Updates source image to [2.4.1](https://github.com/jdeathe/centos-ssh/releases/tag/2.4.1).
+
 ### 2.1.0 - 2018-08-16
 
-- Updates source image to [1.9.0](https://github.com/jdeathe/centos-ssh/releases/tag/1.9.0).
+- Updates source image to [2.4.0](https://github.com/jdeathe/centos-ssh/releases/tag/2.4.0).
 
 ### 2.0.0 - 2018-05-12
 
diff --git a/Dockerfile b/Dockerfile
index c71affd..b49b4ba 100644
--- a/Dockerfile
+++ b/Dockerfile
@@ -3,7 +3,7 @@
 #
 # CentOS-7, Memcached 1.4.
 # =============================================================================
-FROM jdeathe/centos-ssh:2.4.0
+FROM jdeathe/centos-ssh:2.4.1
 
 RUN rpm --rebuilddb \
 	&& yum -y install \
@@ -52,7 +52,7 @@ ENV MEMCACHED_AUTOSTART_MEMCACHED_WRAPPER=true \
 # -----------------------------------------------------------------------------
 # Set image metadata
 # -----------------------------------------------------------------------------
-ARG RELEASE_VERSION="2.1.0"
+ARG RELEASE_VERSION="2.1.1"
 LABEL \
 	maintainer="James Deathe <james.deathe@gmail.com>" \
 	install="docker run \
diff --git a/README.md b/README.md
index 9048ae3..e655810 100644
--- a/README.md
+++ b/README.md
@@ -8,12 +8,12 @@ Docker Image including:
 
 ## Overview & links
 
-The latest CentOS-6 / CentOS-7 based releases can be pulled from the `centos-6` / `centos-7` Docker tags respectively. For production use it is recommended to select a specific release tag - the convention is `centos-6-1.2.0` OR `1.2.0` for the [1.2.0](https://github.com/jdeathe/centos-ssh-memcached/tree/1.2.0) release tag and `centos-7-2.1.0` OR `2.1.0` for the [2.1.0](https://github.com/jdeathe/centos-ssh/tree/2.1.0) release tag.
+The latest CentOS-6 / CentOS-7 based releases can be pulled from the `centos-6` / `centos-7` Docker tags respectively. For production use it is recommended to select a specific release tag - the convention is `centos-6-1.2.1` OR `1.2.1` for the [1.2.1](https://github.com/jdeathe/centos-ssh-memcached/tree/1.2.1) release tag and `centos-7-2.2.1` OR `2.2.1` for the [2.2.1](https://github.com/jdeathe/centos-ssh/tree/2.2.1) release tag.
 
 ### Tags and respective `Dockerfile` links
 
-- `centos-7`,`centos-7-2.1.0`,`2.1.0` [(centos-7/Dockerfile)](https://github.com/jdeathe/centos-ssh-memcached/blob/centos-7/Dockerfile)
-- `centos-6`,`centos-6-1.2.0`,`1.2.0` [(centos-6/Dockerfile)](https://github.com/jdeathe/centos-ssh-memcached/blob/centos-6/Dockerfile)
+- `centos-7`,`centos-7-2.2.1`,`2.2.1` [(centos-7/Dockerfile)](https://github.com/jdeathe/centos-ssh-memcached/blob/centos-7/Dockerfile)
+- `centos-6`,`centos-6-1.2.1`,`1.2.1` [(centos-6/Dockerfile)](https://github.com/jdeathe/centos-ssh-memcached/blob/centos-6/Dockerfile)
 
 Included in the build are the [SCL](https://www.softwarecollections.org/), [EPEL](http://fedoraproject.org/wiki/EPEL) and [IUS](https://ius.io) repositories. Installed packages include [OpenSSH](http://www.openssh.com/portable.html) secure shell, [vim-minimal](http://www.vim.org/), are installed along with python-setuptools, [supervisor](http://supervisord.org/) and [supervisor-stdout](https://github.com/coderanger/supervisor-stdout).
 
@@ -39,7 +39,8 @@ Run up a container named `memcached.pool-1.1.1` from the docker image `jdeathe/c
 $ docker run -d \
   --name memcached.pool-1.1.1 \
   -p 11211:11211/tcp \
-  jdeathe/centos-ssh-memcached:2.1.0
+  --sysctl "net.core.somaxconn=1024" \
+  jdeathe/centos-ssh-memcached:2.2.1
 ```
 
 Now you can verify it is initialised and running successfully by inspecting the container's logs.
@@ -74,8 +75,11 @@ $ docker run \
   --tty \
   --name memcached.pool-1.1.1 \
   --publish 11211:11211/tcp \
+  --sysctl "net.core.somaxconn=1024" \
+  --sysctl "net.ipv4.ip_local_port_range=1024 65535" \
+  --sysctl "net.ipv4.route.flush=1" \
   --env "MEMCACHED_CACHESIZE=32" \
-  jdeathe/centos-ssh-memcached:2.1.0
+  jdeathe/centos-ssh-memcached:2.2.1
 ```
 
 #### Environment Variables
diff --git a/default.mk b/default.mk
index 3264011..3f49c73 100644
--- a/default.mk
+++ b/default.mk
@@ -3,6 +3,9 @@
 define DOCKER_CONTAINER_PARAMETERS
 --name $(DOCKER_NAME) \
 --restart $(DOCKER_RESTART_POLICY) \
+--sysctl "net.core.somaxconn=$(SYSCTL_NET_CORE_SOMAXCONN)" \
+--sysctl "net.ipv4.ip_local_port_range=$(SYSCTL_NET_IPV4_IP_LOCAL_PORT_RANGE)" \
+--sysctl "net.ipv4.route.flush=$(SYSCTL_NET_IPV4_ROUTE_FLUSH)" \
 --env "MEMCACHED_AUTOSTART_MEMCACHED_WRAPPER=$(MEMCACHED_AUTOSTART_MEMCACHED_WRAPPER)" \
 --env "MEMCACHED_CACHESIZE=$(MEMCACHED_CACHESIZE)" \
 --env "MEMCACHED_MAXCONN=$(MEMCACHED_MAXCONN)" \
diff --git a/environment.mk b/environment.mk
index dd1016c..b9cc487 100644
--- a/environment.mk
+++ b/environment.mk
@@ -13,6 +13,11 @@ DOCKER_IMAGE_RELEASE_TAG_PATTERN := ^(1|2|centos-(6-1|7-2))\.[0-9]+\.[0-9]+$
 # Variables
 # -----------------------------------------------------------------------------
 
+# Docker --sysctl settings
+SYSCTL_NET_CORE_SOMAXCONN ?= 1024
+SYSCTL_NET_IPV4_IP_LOCAL_PORT_RANGE ?= 1024 65535
+SYSCTL_NET_IPV4_ROUTE_FLUSH ?= 1
+
 # Docker image/container settings
 DOCKER_CONTAINER_OPTS ?=
 DOCKER_IMAGE_TAG ?= latest
diff --git a/src/etc/systemd/system/centos-ssh-memcached@.service b/src/etc/systemd/system/centos-ssh-memcached@.service
index 143b57d..9def04d 100644
--- a/src/etc/systemd/system/centos-ssh-memcached@.service
+++ b/src/etc/systemd/system/centos-ssh-memcached@.service
@@ -52,13 +52,16 @@ Environment="DOCKER_USER=jdeathe"
 Environment="DOCKER_CONTAINER_OPTS="
 Environment="DOCKER_IMAGE_PACKAGE_PATH=/var/opt/scmi/packages"
 Environment="DOCKER_IMAGE_NAME=centos-ssh-memcached"
-Environment="DOCKER_IMAGE_TAG=2.1.0"
+Environment="DOCKER_IMAGE_TAG=2.1.1"
 Environment="DOCKER_PORT_MAP_TCP_11211=11211"
 Environment="DOCKER_PORT_MAP_UDP_11211=NULL"
 Environment="MEMCACHED_AUTOSTART_MEMCACHED_WRAPPER=true"
 Environment="MEMCACHED_CACHESIZE=64"
 Environment="MEMCACHED_MAXCONN=1024"
 Environment="MEMCACHED_OPTIONS=-U 0"
+Environment="SYSCTL_NET_CORE_SOMAXCONN=1024"
+Environment="SYSCTL_NET_IPV4_IP_LOCAL_PORT_RANGE=1024 65535"
+Environment="SYSCTL_NET_IPV4_ROUTE_FLUSH=1"
 
 # Initialisation: Load image from local storage if available, otherwise pull.
 ExecStartPre=/bin/bash -c \
@@ -88,6 +91,9 @@ ExecStartPre=-/bin/bash -c \
 ExecStart=/bin/bash -c \
   "exec /usr/bin/docker run \
     --name %p.%i \
+    --sysctl \"net.core.somaxconn=${SYSCTL_NET_CORE_SOMAXCONN}\" \
+    --sysctl \"net.ipv4.ip_local_port_range=${SYSCTL_NET_IPV4_IP_LOCAL_PORT_RANGE}\" \
+    --sysctl \"net.ipv4.route.flush=${SYSCTL_NET_IPV4_ROUTE_FLUSH}\" \
     --env \"MEMCACHED_AUTOSTART_MEMCACHED_WRAPPER=${MEMCACHED_AUTOSTART_MEMCACHED_WRAPPER}\" \
     --env \"MEMCACHED_CACHESIZE=${MEMCACHED_CACHESIZE}\" \
     --env \"MEMCACHED_MAXCONN=${MEMCACHED_MAXCONN}\" \
diff --git a/src/opt/scmi/default.sh b/src/opt/scmi/default.sh
index 0643f9c..2ed304c 100644
--- a/src/opt/scmi/default.sh
+++ b/src/opt/scmi/default.sh
@@ -40,6 +40,9 @@ fi
 # Common parameters of create and run targets
 DOCKER_CONTAINER_PARAMETERS="--name ${DOCKER_NAME} \
 --restart ${DOCKER_RESTART_POLICY} \
+--sysctl \"net.core.somaxconn=${SYSCTL_NET_CORE_SOMAXCONN}\" \
+--sysctl \"net.ipv4.ip_local_port_range=${SYSCTL_NET_IPV4_IP_LOCAL_PORT_RANGE}\" \
+--sysctl \"net.ipv4.route.flush=${SYSCTL_NET_IPV4_ROUTE_FLUSH}\" \
 --env \"MEMCACHED_AUTOSTART_MEMCACHED_WRAPPER=${MEMCACHED_AUTOSTART_MEMCACHED_WRAPPER}\" \
 --env \"MEMCACHED_CACHESIZE=${MEMCACHED_CACHESIZE}\" \
 --env \"MEMCACHED_MAXCONN=${MEMCACHED_MAXCONN}\" \
diff --git a/src/opt/scmi/environment.sh b/src/opt/scmi/environment.sh
index 88750c2..bad6865 100644
--- a/src/opt/scmi/environment.sh
+++ b/src/opt/scmi/environment.sh
@@ -30,6 +30,11 @@ DIST_PATH="${DIST_PATH:-./dist}"
 # Number of seconds expected to complete container startup including bootstrap.
 STARTUP_TIME="${STARTUP_TIME:-1}"
 
+# Docker --sysctl settings
+SYSCTL_NET_CORE_SOMAXCONN="${SYSCTL_NET_CORE_SOMAXCONN:-1024}"
+SYSCTL_NET_IPV4_IP_LOCAL_PORT_RANGE="${SYSCTL_NET_IPV4_IP_LOCAL_PORT_RANGE:-1024 65535}"
+SYSCTL_NET_IPV4_ROUTE_FLUSH="${SYSCTL_NET_IPV4_ROUTE_FLUSH:-1}"
+
 # ETCD register service settings
 REGISTER_ETCD_PARAMETERS="${REGISTER_ETCD_PARAMETERS:-}"
 REGISTER_TTL="${REGISTER_TTL:-60}"
diff --git a/src/opt/scmi/service-unit.sh b/src/opt/scmi/service-unit.sh
index 7eb5a95..0cd6062 100644
--- a/src/opt/scmi/service-unit.sh
+++ b/src/opt/scmi/service-unit.sh
@@ -11,6 +11,9 @@ readonly SERVICE_UNIT_ENVIRONMENT_KEYS="
  MEMCACHED_CACHESIZE
  MEMCACHED_MAXCONN
  MEMCACHED_OPTIONS
+ SYSCTL_NET_CORE_SOMAXCONN
+ SYSCTL_NET_IPV4_IP_LOCAL_PORT_RANGE
+ SYSCTL_NET_IPV4_ROUTE_FLUSH
 "
 readonly SERVICE_UNIT_REGISTER_ENVIRONMENT_KEYS="
  REGISTER_ETCD_PARAMETERS
diff --git a/test/shpec/operation_shpec.sh b/test/shpec/operation_shpec.sh
index 8d761a9..4dd91fe 100644
--- a/test/shpec/operation_shpec.sh
+++ b/test/shpec/operation_shpec.sh
@@ -517,8 +517,8 @@ function test_custom_configuration ()
 
 		it "Can disable memcached-wrapper."
 			docker ps \
-				--format "name=memcached.pool-1.1.1" \
-				--format "health=healthy" \
+				--filter "name=memcached.pool-1.1.1" \
+				--filter "health=healthy" \
 			&> /dev/null \
 			&& docker top \
 				memcached.pool-1.1.1 \