ssh&telnet

NetCat网络工具：

root@10.1.1.43:~# nc -h
[v1.10-38]
connect to somewhere: nc [-options] hostname port[s] [ports] ...
listen for inbound: nc -l -p port [-options] [hostname] [port]
options:
-c shell commands as `-e'; use /bin/sh to exec [dangerous!!]
-e filename program to exec after connect [dangerous!!]
-b allow broadcasts
-g gateway source-routing hop point[s], up to 8 设置路由器跃程通信网关，最高可设置8个。
-G num source-routing pointer: 4, 8, 12, ... 设置来源路由指向器，其数值为4的倍数。
-h this cruft
-i secs delay interval for lines sent, ports sca 延时的间隔
-k set keepalive option on socket
-l listen mode, for inbound connects 监听模式,入站连接
-n numeric-only IP addresses, no DNS 直接使用ip地址,而不用域名服务器
-o file hex dump of traffic 指定文件名称，把往来传输的数据以16进制字码倾倒成该文件保存。
-p port local port number 本地端口
-r randomize local and remote ports 随机本地和远程端口
-q secs quit after EOF on stdin and delay of secs
-s addr local source address
-T tos set Type Of Service
-t answer TELNET negotiation
-u UDP mode udp 模式
-v verbose [use twice to be more verbose] 显示过程,vv 更多
-w secs timeout for connects and final net reads 等待连接超时
-z zero-I/O mode [used for scanning] 使用输入/输出模式，只在扫描通信端口时使用。

使用nc -z 192.168.1.6 10-800  扫描ip为 192.168.1.6的10到800的端口是否打开；
然后使用可以发现如果有telnet或者ssh就可以连接了；

ssh
username@192.168.1.6 

scp
news/news.err  username@192.168.1.6:/home/my/dir