Here are several different ways to test a TCP port without telnet.
BASH (man page)
$ cat < /dev/tcp/127.0.0.1/22
SSH-2.0-OpenSSH_5.3
^C
$ cat < /dev/tcp/127.0.0.1/23
| import java.net.InetSocketAddress | |
| import scala.xml.{Elem, XML} | |
| import org.jboss.netty.buffer.ChannelBuffers | |
| import org.jboss.netty.util.CharsetUtil.UTF_8 | |
| import com.twitter.finagle.Service; | |
| import com.twitter.finagle.builder.ClientBuilder; | |
| import com.twitter.finagle.http.{Http, RequestBuilder}; | |
| import org.jboss.netty.handler.codec.http._ | |
| import org.jboss.netty.buffer.ChannelBuffers.wrappedBuffer | |
| import java.net.URL |
Here are several different ways to test a TCP port without telnet.
$ cat < /dev/tcp/127.0.0.1/22
SSH-2.0-OpenSSH_5.3
^C
$ cat < /dev/tcp/127.0.0.1/23
| #!/bin/bash | |
| # run this scripts with `bash emoji-info.sh` or `./emoji-info.sh` | |
| usage() { | |
| cat << EOF | |
| usage: $0 [options] <emoji> | |
| Options: | |
| -h Show this message | |
| -o Octal Escape Sequence |
| package mycompany.myappp.config; | |
| import org.apache.commons.io.IOUtils; | |
| import org.springframework.context.annotation.Configuration; | |
| import org.springframework.http.HttpInputMessage; | |
| import org.springframework.http.HttpOutputMessage; | |
| import org.springframework.http.MediaType; | |
| import org.springframework.http.converter.AbstractHttpMessageConverter; | |
| import org.springframework.http.converter.HttpMessageConverter; | |
| import org.springframework.http.converter.HttpMessageNotReadableException; |
CATF44LT7C-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
| Serial Keys: | |
| FU512-2DG1H-M85QZ-U7Z5T-PY8ZD | |
| CU3MA-2LG1N-48EGQ-9GNGZ-QG0UD | |
| GV7N2-DQZ00-4897Y-27ZNX-NV0TD | |
| YZ718-4REEQ-08DHQ-JNYQC-ZQRD0 | |
| GZ3N0-6CX0L-H80UP-FPM59-NKAD4 | |
| YY31H-6EYEJ-480VZ-VXXZC-QF2E0 | |
| ZG51K-25FE1-H81ZP-95XGT-WV2C0 | |
| VG30H-2AX11-H88FQ-CQXGZ-M6AY4 |
| kind: ClusterRole | |
| apiVersion: rbac.authorization.k8s.io/v1 | |
| metadata: | |
| name: system:aggregated-metrics-reader | |
| labels: | |
| rbac.authorization.k8s.io/aggregate-to-view: "true" | |
| rbac.authorization.k8s.io/aggregate-to-edit: "true" | |
| rbac.authorization.k8s.io/aggregate-to-admin: "true" | |
| rules: | |
| - apiGroups: ["metrics.k8s.io"] |
| #!/bin/bash | |
| ## Generic installation on all nodes | |
| sysctl -w net.ipv4.ip_forward=1 | |
| sed -i 's/#net.ipv4.ip_forward=1/net.ipv4.ip_forward=1/g' /etc/sysctl.conf | |
| sudo sysctl -p /etc/sysctl.conf | |
| swapoff -a | |
| sed -i '2s/^/#/' /etc/fstab |
/etc/pki/ca-trust/source/anchors on your CentOS machineupdate-ca-trust extractwget https://thewebsite.org| #!/usr/bin/env bash | |
| set -e -o pipefail; [[ -n "$DEBUG" ]] && set -x | |
| CERT_DIR="${CERT_DIR:-"/usr/local/share/ca-certificates"}" | |
| function usage() { | |
| echo "Usage: $(basename "$0") [-n clustername] certfile ..." >&2 | |
| } |