vntsd

- virtual network terminal server daemon for Logical Domains

Synopsis

/usr/lib/ldoms/vntsd 

Description

The vntsd daemon is a server that supports connections to the Logical Domains (LDoms) console by using telnet(1). When a telnet session starts, vntsd sends telnet options to the client indicating a willingness to remotely echo characters and to suppress go ahead.

Consoles are organized into groups by the LDoms Manager. Each console group is assigned a unique group name and TCP port number. vntsd uses the group's port number to export access to the consoles within that group. To establish a connection with a console or console group, a user starts a telnet(1) session with the corresponding group's port number. Depending on the number of consoles within that group, vntsd does one of two things:

• If there is only one console in the group, vntsd connects a session to that LDoms console.

• If there are multiple consoles in the group, vntsd prompts the user to select the console to which they would like to connect, as shown in “Multiple-Console Options,” below.

For each console, vntsd provides write access only to the first user connecting to the console. Subsequent users connecting to the console are allowed only to read from the console and wait for write access. When the first user disconnects, write privileges are transferred to the next user waiting in the queue. If a user who does not have write privileges attempts to write to a console, the vntsd displays the following message:

You do not have write access

A user who has no write access can acquire write access forcibly by using the ~w special console command, described in “Special Console Commands,” below.

vntsd can be invoked only with superuser privileges or by someone fitting the appropriate security profile.

Options

The options for vntsd are divided into multiple-console options and console commands.

Multiple-Console Options

The options listed below are supported when there are multiple LDoms consoles in a group. The syntax for the use of these options is:

<hostname>-vnts-<group-name>: <option>

For example:

myhost-vnts-salesgroup: h

The h option invokes help, as described below.

h

Display the following help text:

h -- this help
l -- list of consoles
q -- quit
c{id}, n{name} -- connect to console of domain {id} or domain name

l

List all consoles in the group. For example:

DOMAIN ID       DOMAIN NAME     DOMAIN STATE
0               ldg1            online
1               ldg2            connected
...             ...             ...

The two domain states and their meanings are:

online

No one is connected to the console.

connected

At least one user is already connected to the console.

q

Disconnect from vntsd.

c{id}, n{name}

Connect to specified console. Upon connection, the following message is displayed:

Connecting to console <domain-name> in group <group-name>
Press ~? for control options ....

Special Console Commands

A tilde (~) appearing as the first character of a line is an escape signal that directs vntsd to perform a special console command. The tilde-tilde (~~) sequence outputs a tilde. In conjunction with the initial tilde, vntsd accepts the following special console commands:

~.

Disconnect from the console or console group.

~w

Force write access to the console.

~p

Disconnect from this console, and connect to the console that precedes this console in the list of consoles.

~n

Disconnect from this console, and connect to the console that follows this console in the list of consoles.

~#

Send break.

~^B

Send alternate break.

~?

Display vntsd help, as follows:

~# - Send break
~^B - Send alternate break
~. - Exit from this console
~w - Force write access
~n - Console next
~p - Console previous
~? - Help

Files

/usr/lib/ldoms/vntsd

Binary executable vntsd file.

/usr/lib/ldoms/vntsd.xml

Service management facility (smf(5)) manifest file for vntsd.

Attributes

See attributes(5) for descriptions of the following attributes:

See Also

telnet(1), svccfg(1M), usermod(1M), auth_attr(4), attributes(5), smf(5)

Notes

The vntsd is managed by the service management facility, smf(5), under the service identifier:

svc:/ldoms/vntsd

You can change the following properties using the svccfg(1M) command:

vntsd/vcc_device

Set an instance of the virtual console concentrator (vcc) driver to which vntsd is connected.

vntsd/listen_addr

Set the IP address to which vntsd listens, using the following syntax:

vntsd/listen_addr:"xxx.xxx.xxx.xxx"

...where xxx.xxx.xxx.xxx is a valid IP address. The default value of this property is to listen on IP address 127.0.0.1. Users can connect to a guest console over a network if the value is set to the IP address of the control domain.

---

Note - Enabling network access to a console has security implications. Any user can connect to a console and for this reason it is disabled by default.

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vntsd/timeout_minutes

Set timeout in minutes. vntsd will timeout (close) telnet connection if there is no activity (input or output) on the console. The default value is 0, which disables timeout.

vntsd/authorization

Enable the authorization checking of users and roles for the domain console or consoles that are being accessed. The default value of this property is false to maintain backward compatibility. To enable authorization checking, use the svccfg(1M) command to set the property value to true. While this option is enabled, vntsd listens and accepts connections on localhost. If the listen_addr property specifies an alternate IP address when this option is enabled, vntsd ignores the alternate IP address and continues to listen on localhost. Connections that are initiated from other hosts will also fail. Authorizations are available to access all consoles or console groups, or to access specific consoles or console groups. When the vntsd service is enabled, the following authorization is added to the authorization description database, auth_attr(4):

solaris.vntsd.consoles:::Access All LDoms Guest Consoles::

Add any fine-grained authorizations based on the name of the console group. For example, if the name of the console group to be authorized is ldg1, add the following entry to the auth_attr(4) file:

solaris.vntsd.console-ldg1:::Access Specific LDoms Guest Console::

By default, the authorization to access all consoles is assigned to the root user or role. The superuser, or user with appropriate privileges, can use the usermod(1M) command to assign the required authorization or authorizations to other users or roles.

The following example gives user user1 the authorization to access all domain consoles:

# usermod -A "solaris.vntsd.consoles" user1

The following example gives user user1 the authorization to access the console group named ldg1:

# usermod -A "solaris.vntsd.console-ldg1" user1