HP NonStop SSH 544701-014, Reference Manual

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HP NonStop SSH Reference Manual Introduction
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Components of the SSH2 Software Package
The SSH2 software package consists of the following components:
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The SSH2 component is the central component of the implementation. Depending on the mode it is started in, it
can serve different purposes:
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It implements a server process for the SSH2 protocol. It listens for incoming connections on a specific
TCP/IP port (typically port 22), authenticates the user and the service and then spawns other processes it
communicates with.
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It is opened by the SSHCOM component to maintain the SSH configuration database.
o It is opened by the SFTP or SSH client components to initiate Shell or SFTP-based file transfers to other
platforms running an SSH daemon.
The SSH2 component accesses a user database that contains the following entries for incoming SFTP
connections:
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remote user names
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the mapping of remote user names to Guardian system users
o user’s public keys
o user’s credentials on the system
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selected status information, such as the last time a user accessed the system
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The SSHOSS component implements a Secure Shell client running under OSS to connect to a remote SSH
daemon. It provides Secure Shell sessions as well as TCP and FTP port forwarding capabilities.
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The SSH component implements a Secure Shell client running under Guardian to connect to a remote SSH
daemon. It provides Secure Shell sessions as well as TCP and FTP port forwarding capabilities.
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The SFTPSERV component is started by SSH2 for each SFTP client that connects to SSH2 components. The
SFTPSERV component then handles the file I/O associated with the file transfers initiated by the SFTP client.
Because SFTPSERV is started by the SSH2 component, configuration of SFTPSERV is implicit by the
configuration of the SSH2 component.
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The SFTPOSS component implements an SFTP client running under the OSS personality.
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The SFTP component implements an SFTP client running under the Guardian personality.
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The SSHCOM component allows the maintenance of the SSH user database. To do so, it communicates with
the SSH2 component.
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The PAUTH component is used by SSH2 for authenticating user passwords against the system user base.
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The STN component is a pseudo TTY server providing full screen shell access to remote SSH clients.
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The SCPOSS component is the scp server implementation. It is started on request of a remote scp client via
shell command. The scp client on Guardian/OSS has not been added yet.