ubuntu更新时报错-3B4FE6ACC0B21F32

ubuntu更新了sources.list以后，执行sudo apt-get update -y，报错了：
W: There is no public key available for the following key IDs:
3B4FE6ACC0B21F32
W: There is no public key available for the following key IDs:
3B4FE6ACC0B21F32
W: There is no public key available for the following key IDs:
3B4FE6ACC0B21F32
W: There is no public key available for the following key IDs:
3B4FE6ACC0B21F32
W: There is no public key available for the following key IDs:
3B4FE6ACC0B21F32


如何解决：
sudo apt-key adv --keyserver keyserver.ubuntu.com --recv-keys 3B4FE6ACC0B21F32
还有的会报其他的public key错误，那就仿照上面的，修改下recv-keys继续执行即可。如：
sudo apt-key adv --keyserver keyserver.ubuntu.com --recv-keys 40976EAF437D05B5







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