1、输入下面命令，创建mysql容器时报错

docker run -it\ 
-p 5678:3306\ 
--name=c_mysql\ 
-v $PWD/conf:/etc/mysql/conf.d\ 
-v $PWD/logs:/logs\ 
-v $PWD/data:/var/lib/mysql\ 
-e MYSQL_ROOT_PASSWORD=123456\ 
mysql:5.6

报错：

unknown shorthand flag: 'p' in --p
See 'docker --help'.

原因：命令输入不对，空格没有打好

解决办法：命令与命令之间最好手动空格

建议直接输入：

docker run -id -p 5678:3306 --name=c_mysql -v $PWD/conf:/etc/mysql/conf.d -v $PWD/logs:/logs -v $PWD/data:/var/lib/mysql -e MYSQL_ROOT_PASSWORD=123456 mysql:5.6

总结：如果报错的时候第一时间就仔细的检查命令格式是否正确，也不会浪费那摩多时间。而且这种低级错误百度一般也没有答案，只能找到其他类似的答案，最后还是回到命令上来仔细观察之下，才把问题解决了。所以遇到问题应该自己要先思考，对于这个问题，自己能想到的所有可能造成原因有哪些，有什么可以解决问题的办法，尝试完自己知道的所有方法还不行，在百度也不迟。

2、docker端口映射或启动容器时报

现象：

[root@localhost ~]# docker run -d -p 9000:80 centos:httpd /bin/sh -c /usr/local/bin/start.sh
d5b2bd5a7bc4895a973fe61efd051847047d26385f65c278aaa09e4fa31c4d76
docker: Error response from daemon: driver failed programming external connectivity on endpoint quirky_allen (6bda693d1143657e46bee0300276aa05820da2b21a3d89441e820d1a274c48b6): (iptables failed: iptables --wait -t nat -A DOCKER -p tcp -d 0/0 --dport 9000 -j DNAT --to-destination 172.17.0.2:80 ! -i docker0: iptables: No chain/target/match by that name.
(exit status 1)).

[root@localhost ~]# docker start d5b2bd5a7bc4
Error response from daemon: driver failed programming external connectivity on endpoint quirky_allen (4127da7466709fd45695a1fbe98e13c2ac30c2a554e18fb902ef5a03ba308438): (iptables failed: iptables --wait -t nat -A DOCKER -p tcp -d 0/0 --dport 9000 -j DNAT --to-destination 172.17.0.2:80 ! -i docker0: iptables: No chain/target/match by that name.
(exit status 1))
Error: failed to start containers: d5b2bd5a7bc4

原因:

docker服务启动时定义的自定义链DOCKER由于某种原因被清掉
重启docker服务及可重新生成自定义链DOCKER

Chain PREROUTING (policy ACCEPT)
target     prot opt source               destination        
DOCKER     all  --  0.0.0.0/0            0.0.0.0/0            ADDRTYPE match dst-type LOCAL

Chain INPUT (policy ACCEPT)
target     prot opt source               destination        

Chain OUTPUT (policy ACCEPT)
target     prot opt source               destination        
DOCKER     all  --  0.0.0.0/0           !127.0.0.0/8          ADDRTYPE match dst-type LOCAL

Chain POSTROUTING (policy ACCEPT)
target     prot opt source               destination        
MASQUERADE  all  --  172.17.0.0/16        0.0.0.0/0          
MASQUERADE  tcp  --  172.17.0.2           172.17.0.2           tcp dpt:8080

Chain DOCKER (2 references)
target     prot opt source               destination        
RETURN     all  --  0.0.0.0/0            0.0.0.0/0          
DNAT       tcp  --  0.0.0.0/0            0.0.0.0/0            tcp dpt:8888 to:172.17.0.2:8080
root@router:playbook#iptables -t nat -nL
Chain PREROUTING (policy ACCEPT)
target     prot opt source               destination        
DOCKER     all  --  0.0.0.0/0            0.0.0.0/0            ADDRTYPE match dst-type LOCAL

Chain INPUT (policy ACCEPT)
target     prot opt source               destination        

Chain OUTPUT (policy ACCEPT)
target     prot opt source               destination        
DOCKER     all  --  0.0.0.0/0           !127.0.0.0/8          ADDRTYPE match dst-type LOCAL

Chain POSTROUTING (policy ACCEPT)
target     prot opt source               destination        
MASQUERADE  all  --  172.17.0.0/16        0.0.0.0/0          
MASQUERADE  tcp  --  172.17.0.2           172.17.0.2           tcp dpt:8080

Chain DOCKER (2 references)
target     prot opt source               destination        
RETURN     all  --  0.0.0.0/0            0.0.0.0/0          
DNAT       tcp  --  0.0.0.0/0            0.0.0.0/0            tcp dpt:8888 to:172.17.0.2:8080

解决办法:

重启docker服务后再启动容器

systemctl restart docker
docker start name