The Diskless Node Server: netman

The netman (lsys/net/netman) process manages requests from diskless nodes for access to

The netman process, running on a disked node, receives "request for volunteer" broad-casts from diskless nodes attempting to boot. The netman server looks in its

Isys/net/diskless_list for a diskless node's hexadecimal ID. If the ID appears in the list, the diskless node can read, from netboot, the disked node on which netman runs. To control the distribution of disked node resources in the network, specify which diskless nodes can use a given disked node as a partner. Do this by placing diskless node IDs in the partner's Isys/net/diskless_list.

If a diskless node does not have its own 'node_data.diskless.node_id directory when it boots, netman will create one for it from a template in the disked node's

Isys/dm/startup_templates directory. See Section 3.8 for more information about node start-up directories.

The netman server runs as a background process from a start-up file. The command line that executes netman is in the start-up files that arrives with your system. Remove the pound sign (#) at the beginning of the command line to enable the process. The netman server will execute from the start-up script when the node is rebooted. You may start the process from the DM command line as shown in the next section.

NOTE: We do not recommend that you run netman on an internet routing node. Network traffic between a diskless node and the routing node would compete with the internet traffic on the routing node, slowing both the internet traffic and the response time of the diskless node.

Starting and Stopping netman

To start netman from the DM command line, enter the following command:

Command: cps Isys/net/netman

The server process begins immediately and persists after logout. Another way to start net-man is to uncomment the following line in the appropriate start-up file for the disked node:

# cps /sys/net/netman

The server process begins when the node is booted, and continues under normal conditions until it is intentionally stopped with the shell command sigp, as shown:

% sigp netman -q

With both start-up methods described above, the process stops running if the node is shut down intentionally or because the system crashes. Restart the process if it stops running by rebooting the node, or by entering the cps command from the DM command line.

Special Considerations

For a temporary fix, you can use netman if youdisked node malfunctions. To do this you must shutdown and reboot your node diskless. The netman process allows any disked node to continue functioning even if its disk becomes nonfunctional.

3-42 Administering Nodes in the Network

For this temporary procedure:

1. Determine the node ID of any node running netman. (You may want to start the netman process on a disked node in the same loop as the now diskless node.) 2. Use the DM command shut on the node that you want to boot diskless.

3. Then type the following at the Mnemonic Debugger prompt:

> re

> di n node_id {node_id is the node ID of the node running netman}

> ex domain os

Network Partner ID nnnn

In this procedure, netman bypasses Isys/net/diskless_list. You don't need to edit the list to get the node back in the network. When you use this procedure, netman creates a

'node_data/startup[.type) file for the node with disk problems.

3.13.4 The Tablet Server: sbpl

The Tablet Server (/sys/dm/sbpl) supports tablets that conform to the binary output mode used by Summa graphics Corporation tablets. To use a tablet, enable the Tablet Server sup-port program in the appropriate start-up file for the node. The server process sends a con-trol character to the tablet bit pad. An operating system program then provides the actual bit-pad support. The process started in the start-up file stops running when the operating system has taken control.

Starting the Tablet Server

To start the Tablet Server, uncomment the following line in the appropriate start-up file:

# cps /sys/dm/sbpl /dev/si02 1

To use a different SIO line, change the "2" in the command to the desired number. The letter "I" indicates the mode and sampling rate selector that is sent to the tablet. You may change this mode to one of the other modes described in the Summagraphics Corporation Bit Pad One User's Manual (Form 64).

Special Considerations

The bit-pad support is internal to the operating system, and the server mentioned here only enables the operating system support and then stops. Therefore, the ps command does not show a process for the bit pad. To check on a bit-pad process, use the tcU com-mand on the SIO line to which the bit pad is connected, and check that -bp_enable is true. The bit-pad support program is running properly if the tctl output contains the fol-lowing line:

bp_enable: true