错误如下：
tiger@ubuntu:~/Desktop/work$ sudo apt-get install openssh-server [sudo] password for tiger: Reading package lists... Done Building dependency tree Reading state information... Done Some packages could not be installed. This may mean that you have requested an impossible situation or if you are using the unstable distribution that some required packages have not yet been created or been moved out of Incoming. The following information may help to resolve the situation: The following packages have unmet dependencies: openssh-server: Depends: openssh-client (= 1:5.3p1-3ubuntu3) but 1:5.3p1-3ubuntu4 is to be installed E: Broken packages
输入如下命令即可：
sudo apt-get install openssh-client=1:5.3p1-3ubuntu3
然后出现下面的执行过程：
Reading package lists... Done Building dependency tree Reading state information... Done Suggested packages: libpam-ssh keychain openssh-blacklist openssh-blacklist-extra The following packages will be DOWNGRADED: openssh-client 0 upgraded, 0 newly installed, 1 downgraded, 0 to remove and 299 not upgraded. Need to get 761kB of archives. After this operation, 0B of additional disk space will be used. Do you want to continue [Y/n]? y Get:1 http://us.archive.ubuntu.com/ubuntu/ lucid/main openssh-client 1:5.3p1-3ubuntu3 [761kB] Fetched 761kB in 1min 48s (7,003B/s) dpkg: warning: downgrading openssh-client from 1:5.3p1-3ubuntu4 to 1:5.3p1-3ubuntu3. (Reading database ... 124425 files and directories currently installed.) Preparing to replace openssh-client 1:5.3p1-3ubuntu4 (using .../openssh-client_1%3a5.3p1-3ubuntu3_i386.deb) ... Unpacking replacement openssh-client ... Processing triggers for man-db ... Setting up openssh-client (1:5.3p1-3ubuntu3) ... tiger@ubuntu:~/Desktop/work$ sudo apt-get install openssh-server Reading package lists... Done Building dependency tree Reading state information... Done Suggested packages: rssh molly-guard openssh-blacklist openssh-blacklist-extra The following NEW packages will be installed: openssh-server 0 upgraded, 1 newly installed, 0 to remove and 299 not upgraded. Need to get 285kB of archives. After this operation, 778kB of additional disk space will be used. Get:1 http://us.archive.ubuntu.com/ubuntu/ lucid/main openssh-server 1:5.3p1-3ubuntu3 [285kB] Fetched 285kB in 1min 13s (3,866B/s) Preconfiguring packages ... Selecting previously deselected package openssh-server. (Reading database ... 124425 files and directories currently installed.) Unpacking openssh-server (from .../openssh-server_1%3a5.3p1-3ubuntu3_i386.deb) ... Processing triggers for ureadahead ... ureadahead will be reprofiled on next reboot Processing triggers for ufw ... Processing triggers for man-db ... Setting up openssh-server (1:5.3p1-3ubuntu3) ... Creating SSH2 RSA key; this may take some time ... Creating SSH2 DSA key; this may take some time ... * Stopping OpenBSD Secure Shell server sshd [ OK ] ssh start/running, process 10119 tiger@ubuntu:~/Desktop/work$