HP OpenVMS Systems Documentation
Compaq TCP/IP Services for OpenVMS
If you want to have multiple OpenVMS cluster nodes sharing the same CLIENT.PCY file and the nodes have identical interface names, a conflict will arise if you simply define TCPIP$DHCP_CONFIG to a common directory shared between the systems.
For example, if two systems in your cluster both have an interface named SE0 under DHCP control, to configure for this situation:
You can use the TCPIP$DHCP_SIGNAL utility to signal the DHCP client to:
Table 8-5 shows the commands available with the TCPIP$DHCP_SIGNAL utility:
|DHCPSIGHUP||Causes the ASCII configuration files to be read again and then translates the TCPIP$DHCP_DEBUG and TCPIP$DHCP_LOG_LEVEL logicals.|
|DHCPSIGTERM||Causes an orderly shutdown of DHCP client. Use this command cautiously, as active lease and timer information is lost when you signal the DHCP client to shutdown. As a consequence, when you again start up the DHCP client, the system could be running with an expired lease.|
|DHCPSIGUSR1||Causes diagnostic state information to be written to the TCPIP$DHCP_CLIENT_RUN.LOG file.|
You can use TCP/IP management commands to:
The TCP/IP command SET INTERFACE temporarily puts an interface under DHCP control. It does not make any change to the TCPIP$CONFIGURATION data base.
The format of the command is:
SET INTERFACE ifname/DHCP [/[NO]PRIMARY]
In this format, ifname is the name of the interface; for example, SE0.
You must enter the SET NOINTERFACE command on the interface before entering a SET INTERFACE/DHCP.
After you enter this command, the interface receives a new IP address from the DHCP server, but the information stored in the TCPIP$CONFIGURATION.DAT file is unchanged. For example, if you issue the TCP/IP command SHOW CONFIGURATION INTERFACE for the interface you see the IP address you had set up for the interface before you temporarily configured the interface. In addition, when you stop and restart TCP/IP Services, the interface will have the previously assigned IP address.
If you want the interface to be permanently under DHCP control, you
must either run the TCPIP$CONFIG.COM command procedure to put the
interface under DHCP control or enter the SET CONFIGURATION INTERFACE
ifname/DHCP command. Compaq recommends that you run the
TCPIP$CONFIG.COM command procedure.
8.5.2 Permanently Configuring Interfaces
The TCP/IP command SET CONFIGURATION INTERFACE /DHCP configures an interface to be under DHCP control by adding or changing an entry in the TCPIP$CONFIGURATION database. After entering this command, every time TCPIP$STARTUP.COM is run the DHCP client is invoked to configure the interface.
Note that this command does not change the current run-time configuration of the interface. For any changes to the TCPIP$CONFIGURATION database to take effect, you must run $TCPIP$STARTUP or enter a TCP/IP command START COMMUNICATION/INITIALIZE.
The format of the command is:
SET CONFIGURATION INTERFACE ifname/DHCP [/[NO]PRIMARY]
In this format, ifname is the name of the interface; for example, SE0.
The optional qualifier /PRIMARY indicates that the interface is to be the primary DHCP client interface. (See Section 8.1.1 for a description of the DHCP client primary interface.) TCP/IP Services issues an error if one of the other interfaces has the primary designation.
/NOPRIMARY indicates that the interface is no longer to be marked as the primary DHCP client interface. It is not an error if turning off this option leaves no primary DHCP interfaces, because a primary DHCP interface is not required.
You do not need to issue this command because TCPIP$CONFIG executes the
command for you when you put an interface under DHCP control.
8.6 Using the SHOWDHC Utility
TCP/IP Services provides the SHOWDHC utility for displaying the contents of an interface parameter file.
The SHOWDHC utility displays data stored in an ifname.DHC file.
The format of the SHOWDHC utility command is as follows:
In this format, filename is the name of an ifname.DHC file.
The format of the SHOWDHC output is a single line in the format of the DHCPCAP. file. For more information on the format of the DHCPCAP. file, refer to Section 18.104.22.168. Example 8-2 shows typical output from the SHOWDHC utility.
|Example 8-2 SHOWDHC Sample Output|
$ SHOWDHC SE0.DHC se0.dhc: ht=1:ha=08.00.2b.2a.de.a8:sa=10.10.2.3:yi=10.10.2.101:sm=255.255.255.0:gw=10.10. 2.66:ds=10.10.2.11:ho=rufus:dn=lkg.dec.com:ba=10.10.2.255:lt=1200:sv=10.10.2.3: t1=600:t2=1050:
The Bootstrap Protocol (BOOTP) server answers network bootstrap requests from diskless workstations and other network devices such as routers, terminal servers, and network switching equipment. When it receives such a request, the BOOTP server looks up the client's address in the BOOTP database file.
The Trivial File Transfer Protocol (TFTP) handles the file transfer from a TFTP server to a diskless client or other remote system. The client initiates the file transfer. TFTP is described in Chapter 10.
Because BOOTP is a subset of DHCP, you cannot enable both BOOTP and DHCP on the same host.
This chapter reviews key concepts and describes:
The BOOTP server answers client requests for diskless client configuration by sending address and file name information to the client. When the client receives this information from the BOOTP server, it initiates a file transfer using the TFTP protocol.
When planning BOOTP, you need to make decisions about the network
configuration and the local BOOTP service.
9.2.1 Network Configuration Decisions
Before you start to configure BOOTP, consider the following:
For security purposes, the server runs as an unprivileged image that can access only the directories and files for which it has read access.
Compaq recommends that you safeguard your system's normal file protection mechanisms from unauthorized access. In particular, ensure the security of system files.
The BOOTP server runs as the nonprivileged OpenVMS user account TCPIP$BOOTP. When you set up BOOTP, follow these security procedures:
To set up the BOOTP server software, run TCPIP$CONFIG (see the Compaq TCP/IP Services for OpenVMS Installation and Configuration manual).
The procedure creates:
The following sections describe how to manage the BOOTP service.
9.4.1 Enabling and Disabling BOOTP
To enable and disable BOOTP, use these commands:
To check whether these services are enabled or disabled, enter the following commands:
The following examples show how to use the SHOW SERVICE command to get information about BOOTP.
TCPIP> SHOW SERVICE BOOTP Service Port Proto Process Address State BOOTP 67 UDP TCPIP$BOOTP 0.0.0.0 Enabled
TCPIP> SHOW SERVICE BOOTP /FULL Service: BOOTP State: Enabled Port: 67 Protocol: UDP Address: 0.0.0.0 Inactivity: 5 User_name: TCPIP$BOOTP Process: TCPIP$BOOTP Limit: 1 Active: 1 Peak: 1 File: TCPIP$SYSTEM:TCPIP$BOOTP_RUN.COM Flags: Listen Socket Opts: Rcheck Scheck Receive: 0 Send: 0 Log Opts: Acpt Actv Dactv Conn Error Exit Logi Logo Mdfy Rjct TimeO Addr File: SYS$SYSDEVICE:[TCPIP$BOOTP]TCPIP$BOOTP_RUN.LOG Security Reject msg: not defined Accept host: 0.0.0.0 Accept netw: 0.0.0.0
Table 9-1 summarizes the BOOTP management commands.
|CONVERT/VMS BOOTP||Populates an existing BOOTP database with entries from a UNIX /etc/bootptab file.|
|CREATE BOOTP||Creates an empty BOOTP database.|
|SET BOOTP||Adds or modifies client entries to the BOOTP database.|
|SHOW BOOTP||Displays client information from the BOOTP database.|
|ENABLE SERVICE BOOTP||Dynamically enables the BOOTP service.|
|DISABLE SERVICE BOOTP||Dynamically disables the BOOTP service.|
|SET CONFIGURATION ENABLE SERVICE BOOTP|
|Sets the configuration database to enable BOOTP at product startup.|
|SET CONFIGURATION DISABLE SERVICE BOOTP|
|Sets the configuration database to disable BOOTP at product startup.|
|SET SERVICE BOOTP||Configures the BOOTP service in the services database.|
|SET NOSERVICE BOOTP||Disables the BOOTP service in the configuration database.|
|SHOW SERVICE BOOTP||Displays BOOTP server information stored in the services database.|
Table 9-2 lists the logical names you can use to manage the BOOTP software.
|TCPIP$BOOTP||Points to the location of the BOOTP database file.|
|TCPIP$TFTP_ROOT||Defines a concealed device. Points to the TFTP data storage tree, for example, SYS$SYSDEVICE:[TCPIP$TFTP_ROOT.].|
|TCPIP$BOOTP_TRACE||Displays the client hardware address for every incoming BOOTP request and response to requests.|
The BOOTP service can be shut down and started independently. This is useful when you change parameters or logical names that require the service to be restarted. The following files are provided:
To preserve site-specific parameter settings and commands, you can create the following files. These files are not overwritten when you reinstall TCP/IP Services:
If you choose to configure BOOTP while configuring TCP/IP Services, TCPIP$CONFIG creates an empty BOOTP database.
If you need to create it manually, use the TCP/IP management command CREATE BOOTP. This command creates the file SYS$SYSTEM:TCPIP$BOOTP.DAT. The command uses the logical name TCPIP$BOOTP to point to the BOOTP database file. To create a separate database, perhaps in a different disk directory or with a different file name, modify this logical name.
To create a temporary, separate, and empty BOOTP file, you can use a
process-specific logical name. However, Compaq does not recommend
creating separate or private BOOTP databases because the TCPIP$BOOTP
user account requires read access to the database file.
9.5.1 Populating the BOOTP Database
For each BOOTP client in the BOOTP database, use the SET BOOTP command to enter the following required information:
To populate the BOOTP database with client entries, use these commands:
You can use the BOOTP client information in an existing UNIX boot file. The CONVERT/VMS BOOTP command populates the existing BOOTP database with entries from a BIND formatted UNIX /etc/bootptab file.
Before you enter CONVERT/VMS BOOTP, define the logical name TCPIP$BOOTP. The CONVERT/VMS BOOTP command uses it to determine the directory and file name for the database. Enter the following command:
$ DEFINE /SYSTEM TCPIP$BOOTP SYS$COMMON:[SYSEXE]TCPIP$BOOTP.DAT
If you do not define TCPIP$BOOTP, the database is created as [current_directory]TCPIP$BOOTP.DAT.
To populate the BOOTP database by using entries in a UNIX /etc/bootptab file, follow these steps:
TCPIP> CONVERT /VMS BOOTP
The CONVERT/VMS BOOTP command has the following format:
CONVERT/VMS BOOTP source_file /ADD_HOST /FILE=sys_image_file
In this command format: