sshd不能開啟 - Linux

請問一下
我打dpkg -l | grep ssh
出現
ii libssh-4 0.5.2-1
tiny C SSH library
ii openssh-client 1:5.9p1-5ubuntu1
secure shell (SSH) client, for secure access to remote machines
ii openssh-server 1:5.9p1-5ubuntu1
secure shell (SSH) server, for secure access from remote machines
ii python-paramiko 1.7.7.1-2
Make ssh v2 connections with Python
ii ssh 1:5.9p1-5ubuntu1
secure shell client and server (metapackage)
ii ssh-askpass-gnome 1:5.9p1-5ubuntu1
interactive X program to prompt users for a passphrase for ssh-add
ii ssh-import-id 2.10-0ubuntu1
securely retrieve an SSH public key and install it locally


看來openssh-server有安裝好
可是當我打 sudo service sshd start
總是得到 sshd: unrecognized service

為什麼會這樣呢?

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