View Source net_adm (kernel v10.0.1)
Various Erlang net administration routines.
This module contains various network utility functions.
Files
File .hosts.erlang
consists of a number of host names written as Erlang terms.
It is looked for in the current work directory, the user's home directory, and
$OTPROOT
(the root directory of Erlang/OTP), in that order.
The format of file .hosts.erlang
must be one host name per line. The host
names must be within quotes.
Example:
'super.eua.ericsson.se'.
'renat.eua.ericsson.se'.
'grouse.eua.ericsson.se'.
'gauffin1.eua.ericsson.se'.
^ (new line)
Summary
Functions
Returns the official name of Host
, or {error, Host}
if no such name is
found. See also inet
.
Reads file .hosts.erlang
, see section Files. Returns the
hosts in this file as a list. Returns {error, Reason}
if the file cannot be
read or the Erlang terms on the file cannot be interpreted.
Returns the name of the local host. If Erlang was started with command-line flag
-name
, Name
is the fully qualified name.
Equivalent to names(net_adm:localhost())
.
Returns the names and associated port numbers of the Erlang nodes that epmd
registered at the specified host.
Sets up a connection to Node
. Returns pong
if it is successful, otherwise
pang
.
Equivalent to world(silent)
.
Calls names(Host)
for all hosts that are specified in the Erlang
host file .hosts.erlang
, collects the replies, and then evaluates
ping(Node)
on all those nodes. Returns the list of all nodes that
are successfully pinged.
Equivalent to world_list(Hosts, silent)
.
Same as world/0,1
, but the hosts are specified as argument
instead of being read from .hosts.erlang
.
Types
-type verbosity() :: silent | verbose.
Functions
-spec dns_hostname(Host) -> {ok, Name} | {error, Host} when Host :: atom() | string(), Name :: string().
Returns the official name of Host
, or {error, Host}
if no such name is
found. See also inet
.
-spec host_file() -> Hosts | {error, Reason} when Hosts :: [Host :: atom()], Reason :: file:posix() | badarg | terminated | system_limit | {Line :: integer(), Mod :: module(), Term :: term()}.
Reads file .hosts.erlang
, see section Files. Returns the
hosts in this file as a list. Returns {error, Reason}
if the file cannot be
read or the Erlang terms on the file cannot be interpreted.
-spec localhost() -> Name when Name :: string().
Returns the name of the local host. If Erlang was started with command-line flag
-name
, Name
is the fully qualified name.
-spec names() -> {ok, [{Name, Port}]} | {error, Reason} when Name :: string(), Port :: non_neg_integer(), Reason :: address | file:posix().
Equivalent to names(net_adm:localhost())
.
-spec names(Host) -> {ok, [{Name, Port}]} | {error, Reason} when Host :: atom() | string() | inet:ip_address(), Name :: string(), Port :: non_neg_integer(), Reason :: address | file:posix().
Returns the names and associated port numbers of the Erlang nodes that epmd
registered at the specified host.
Similar to epmd -names
, see erts:epmd
.
Returns {error, address}
if epmd
is not operational.
Example:
(arne@dunn)1> net_adm:names().
{ok,[{"arne",40262}]}
-spec ping(Node) -> pong | pang when Node :: atom().
Sets up a connection to Node
. Returns pong
if it is successful, otherwise
pang
.
-spec world() -> [node()].
Equivalent to world(silent)
.
Calls names(Host)
for all hosts that are specified in the Erlang
host file .hosts.erlang
, collects the replies, and then evaluates
ping(Node)
on all those nodes. Returns the list of all nodes that
are successfully pinged.
If Arg == verbose
, the function writes information about which nodes it is
pinging to stdout
.
This function can be useful when a node is started, and the names of the other network nodes are not initially known.
Returns {error, Reason}
if host_file/0
returns {error, Reason}
.
Equivalent to world_list(Hosts, silent)
.
Same as world/0,1
, but the hosts are specified as argument
instead of being read from .hosts.erlang
.