snode_link

Purpose:

Transfer variables from/to remote nodes.

Enter:

snode_link  <filename> [name=task_name] [host=hostname]  [direction=push|pull] &

Where:

filename

Specify a filename that contains the desired list of local and remote CyFlex variables.

name

Optional but required on all secondary instances. Specify the name to register this task with the operating system.  The default value is “node_link”. Each instance must have a unique name.

host

Optional. Specify the IP address or hostname of the remote computer.  

direction

Optional. Specify ‘push’ or ‘pull’ to indicate the direction of data transfer.  The default is to ‘pull’ data from the remote node.

Example:

snode_link  /specs/node_link_specs.123  &
The above starts ‘snode_link’ on the local node accessing the CyFlex variables specified in the file node_link_specs.123.  The task name of “snode_link” is registered with the operating system.

snode_link  node_link.settings  direction=push  host=xyznode27  &
The above starts ‘snode_link’ on the local node and move data to xyznode27.  The local computer must be able to resolve the host name into an IP address.

Notes:

A maximum of 1200 variables may be specified in each file. These variables will be transferred in blocks of 6 and up to 200 blocks can be transferred by one instance of snode_link.  If multiple transfer rates and multiple remote nodes are defined in one file, the maximum number may be slightly less than 1200 since all blocks may not contain a full count.

It is required that all nodes, remote and local,  have the connection server (connsrvr) application running and that the remote nodes have “small_sm” running.  In addition, the connection server spec file must be properly configured on each end. 

This program is normally spawned via the go script. Multiple copies may be spawned if links to different nodes using separate specification files are desired.

The following is an example specification file linking to more than one node.

Standard CyFlex intervals may be used beginning with CyFlex version 6.3.

         # keyword           host name         transfer_interval  
         @HOSTNAME   CMD_LINE             SLO  
                                           ^–this is replaced by the host= option value
 
         # fetched_variable(remote node)  target variable (this node)  
               cell_2_token                               my_token                               
 
      The following is an example specification file linking to a node via it’s  
      ip address or hostname.  
        # keyword           host name         transfer_interval  
         @HOSTNAME  123.45.67.89             60[sec]  
 
         # fetched_variable(remote node)  target variable (this node)  
         barometer                               barometer  
         vp_central                               vap_pa  

NOTE: Beginning with CyFlex version 6.3 the transfer interval can be given as a time value with units, an event name, or one of the standard CyFlex execution rates such as FAS, MED, SLO, etc.

See Also:

connsrvr, Connection Server Setup, Internodal Communications Tasks Reference, snl_test, csdump