我正在尝试在Ubuntu 14.04上安装Cassandra,在运行以下命令时遇到问题:sudo apt-get install cassandra
。
Reading package lists... Done
Building dependency tree
Reading state information... Done
Package cassandra is not available, but is referred to by another package.
This may mean that the package is missing, has been obsoleted, or is only available from another source
E: Package 'cassandra' has no installation candidate
请帮我解决这个问题。我尝试了一些链接,但都没有成功。我需要在我的电脑上安装cassandra。