1. 报错现象

报错信息:

Memory limit should be smaller than already set memoryswap limit, 
update the memoryswap at the same time

当对容器执行docker update时发生报错

root@ubuntu20:~# docker update --memory 300m prod_v1
Error response from daemon: Cannot update container 3554652f8b3ce79bcacbb6042a249f9e7d10154d500eb2a2feb9baf91862b00d: Memory limit should be smaller than already set memoryswap limit, update the memoryswap at the same time

2. 解决方法1

docker update --memory 300m --memory-swap -1 prod_v1

3. 解决方法2

重建容器,在创建时指定–memory,之后再扩展就不会报错了
新建容器

docker run -it -d --name container4 --memory 256m nginx

扩展容器

docker update --memory 512m container4