(PAC Manager is an open source graphical user interface (GUI) based tool that can be used to configure and manage remote SSH/Telnet connections. It supports Remote Desktop Protocol (RDP), Virtual Network Computing (VNC), macros, cluster connections, local execution before/after connection, EXPECT regular expressions and many more targets. It can display connections in a tab or in a separate window, and also gives a tell icon to access your configured connections. I have been using ubuntu for a long time. I don’t need GNS3 because I am learning the network. However, when GNS3 does not have SecureCRT, I have always used the system’s own terminal. I only use it to connect GNS3 and linux, and I haven't tried anything else. Personally feel more powerful than SecureCRT, and it is also open source, .. including deb, rpm, tar.gz packages)