一／scp限速1M
＃scp -l 1000 文件名 账号@远程机器IP
此时的传输速率就是1M／8＝100K左右
二／rsync是（限制为 100k Bytes/s）：
＃rsync -auvzP--bwlimit=100 本地的文件 远程的文件
参数说明：
v：详细提示
a：以archive模式操作，复制目录、符号连接，等价于 -rlptgoD 。
z：压缩
u：只进行更新，防止本地新文件被重写，注意两者机器的时钟的同时
P：是综合了--partial --progress两个参数，
所以此时的rsync支持了断点续传
[liujianzuo@ow2 201512]$ rsync -avz --bwlimit=500 -e 'ssh -p10001' 2015-12-01-access_wap.log ffff@4.5.2.42:/root/log_wap
The authenticity of host '[124.205.209.42]:10001 ([124.205.209.42]:10001)' can't be established.
RSA key fingerprint is 33:61:43:8a:ca:34:3c:f0:56:45:1a:20:7f:0e:b0:8b.
Are you sure you want to continue connecting (yes/no)? yes
Warning: Permanently added '[124.205.209.42]:10001' (RSA) to the list of known hosts.
root@124.205.209.42's password:
sending incremental file list
2015-12-01-access_wap.log
sent 13,951,993 bytes received 34 bytes 416,478.42 bytes/sec
total size is 172,036,811 speedup is 12.33
[liujianzuo@ow2 201512]$