W: http://mirrors.163.com/ubuntu/dists/precise-security/InRelease: Signature by key 630239CC130E1A7FD81A27B140976EAF437D05B5 uses weak digest algorithm (SHA1) W: http://mirrors.163.com/ubuntu/dists/precise-updates/InRelease: Signature by key 630239CC130E1A7FD81A27B140976EAF437D05B5 uses weak digest algorithm (SHA1) W: http://mirrors.163.com/ubuntu/dists/precise-proposed/InRelease: Signature by key 630239CC130E1A7FD81A27B140976EAF437D05B5 uses weak digest algorithm (SHA1) W: http://mirrors.163.com/ubuntu/dists/precise-backports/InRelease: Signature by key 630239CC130E1A7FD81A27B140976EAF437D05B5 uses weak digest algorithm (SHA1) W: http://mirrors.163.com/ubuntu/dists/precise/Release.gpg: Signature by key 630239CC130E1A7FD81A27B140976EAF437D05B5 uses weak digest algorithm (SHA1)