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If queries from a client to an OpenVMS SNMP server are consistently timing out, consider solutions on either the client or server side. For information about checking the client side, refer to the Compaq TCP/IP Services for OpenVMS SNMP Programming and Reference guide.
On the server:
Before making extensive modifications to either the client or the
server, consider analyzing the network load for congestion problems.
13.6.7 Disabling SNMP OPCOM Messages
To disable OPCOM messages for SNMP, enter the following command sequence:
TCPIP> SET SERVICE SNMP /LOG=NOALL TCPIP> DISABLE SERVICE SNMP TCPIP> ENABLE SERVICE SNMP |
Be aware that when you disable OPCOM messages, you may be suppressing information that is useful for solving problems.
Part 4 describes how to set up popular networking end-user applications and includes the following chapters:
The TCP/IP Services product includes and implementation of the TELNET end-user application.
This chapter describes how to set up your host as a TELNET server.
For information about using TELNET, see the DIGITAL TCP/IP Services for OpenVMS User's Guide guide. For information about using the TELNET print symbiont, see Chapter 23.
This chapter describes:
Managing TELNET includes the following tasks:
The TELNET service can be shut down and started independently of TCP/IP Services. 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, create the following files. These files are not overwritten when you reinstall TCP/IP Services:
Table 14-1 lists the logical names you can use in managing the TELNET service.
| Logical Name | Description |
|---|---|
| TCPIP$TELNET_VTA | Enables TELNET virtual terminals. |
Hosts typically run a TELNET server with TELNET client software. Users on client hosts need valid accounts on server hosts before using TELNET to establish a remote session.
If your local host is to be a TELNET server, create OpenVMS accounts
for remote users. You can create several individual accounts or one
account that many remote users will share.
14.1.4 Creating and Deleting Sessions
You can create and delete TELNET sessions from within a command procedure or interactively. Enter the DCL command TELNET with the /CREATE_SESSION or /DELETE_SESSION qualifier. These qualifiers have the same function as the following commands:
TELNET> CREATE_SESSION host port dev-unit |
TELNET> DELETE_SESSION dev-unit |
For example:
$ TELNET /CREATE_SESSION TS405 2002 902 |
You can create a TELNET device that times out after a specified idle period then reconnects when data is written to it. Use the /TIMEOUT qualifier to specify the idle time and the reconnection interval, as described in the following table:
| Qualifier | Description |
|---|---|
| /TIMEOUT |
Creates a TELNET device that has the following connection attributes:
|
| /NOTIMEOUT | Creates a TELNET device that breaks the connection when the device is finally deassigned (the last channel assignment is deassigned). |
To display login and logout messages at the operator's console and log file, enter:
TCPIP> SET SERVICE TELNET /LOG=(LOGIN,LOGOUT) |
IBM 3270 Information Display System (IDS) terminal emulation (TN3270) lets users make connections to hosts that use IBM 3270 model terminals.
TN3270 has default IBM 3270 IDS function assignments for DIGITAL keyboards. In addition, users can make their own assignments and might ask you for help. TCP/IP Services provides EBCDIC-to-DMCS and DMCS-to-EBCDIC translation tables you can customize. Appendix B describes how to customize and rebuild these translation tables.
For more information about using TN3270, enter the following DCL command:
$ HELP TN3270 |
To improve TELNET performance, try modifying some of the internet
parameters. These changes might also decrease the use of system
resources.
14.2.1 TELNET Characteristics That Affect Performance
The settings for the TELNET systemwide characteristics might affect TCP/IP Services and TELNET performance. To display the TELNET systemwide characteristics, enter:
TCPIP> SHOW SERVICE TELNET /FULL |
The command generates a display similar to the following:
Service: TELNET State: Enabled Port: 23 Protocol: TCP Address: 0.0.0.0 Inactivity: 1 User_name: Process: not defined Limit:30 Active: 1 Peak: 4 File: not defined Flags: Listen Priv Rtty Socket Opts: Keepalive Receive: 3000 Send: 3000 Log Opts: Actv Dactv Conn Error Logi Logo Mdfy Rjct Addr File: not defined Security Reject msg: not defined Accept host: 0.0.0.0 Accept netw: 0.0.0.0 |
The TELNET server sends the following error message for a TELNET login request that cannot be satisfied:
SS$_EXQUOTA |
This error is due to insufficient local resources, such as:
TCPIP> SHOW SERVICE TELNET |
PEAK=limit |
TCPIP> SET SERVICE TELNET /LIMIT=n |
Verify that the CHANNELCNT parameter (in SYSGEN) is larger than the number of simultaneous TELNET and RLOGIN sessions that you plan to support.
The File Transfer Protocol (FTP) software transfers files between "nontrusted" hosts. Nontrusted hosts require user name and password information for remote logins.
The TCP/IP Services product includes an implementation of the FTP end-user applications.
This chapter describes:
For information on using FTP, see the DIGITAL TCP/IP Services for OpenVMS User's Guide.
15.1 Managing FTP
Managing FTP consists of the the following tasks:
After FTP is configured by TCPIP$CONFIG, the postinstallation configuration procedure, it is started automatically when TCP/IP Services is started.
To stop any new connections without losing existing connections, disable the FTP server interactively using the SET NOSERVICE command. To disable FTP when TCP/IP Services starts, use the SET CONFIGURATION NOSERVICE command.
See the Compaq TCP/IP Services for OpenVMS Management Command Reference for descriptions of the SET SERVICE and SET
CONFIGURATION SERVICE commands.
15.1.2 Configuring Anonymous FTP
Anonymous FTP is an FTP session in which a user logs in to the remote server using the user name ANONYMOUS and, by convention, the user's real user name as the password.
On the local FTP server, local users can access files without password authentication. Remote users do not require an account. File access is controlled by regular OpenVMS access restrictions.
When you use TCPIP$CONFIG to establish an ANONYMOUS account, a new account is created with the UIC [TCPIP,ANONYMOUS] (numeric [3375,xx]), user name ANONYMOUS, account ANONY, default directory SYS$SYSDEVICE:[ANONYMOUS], and the following types of login access:
| network | full access |
| batch | no access |
| local | no access |
| dialup | no access |
| local | no access |
The usual OpenVMS file protection codes restrict file access for inbound anonymous FTP sessions to this directory, its subdirectories, and files with an owner attribute of [TCPIP,ANONYMOUS].
When the ANONYMOUS account has been created, a remote FTP client can:
You can set up guest and public directories for bulletin board or group interest. Make sure the directory protections are set to read-only or read/write, as needed.
In the following example, UNIX user ubird connects to the ANONYMOUS account on OpenVMS host TRAGOPAN. TRAGOPAN asks for ubird 's password, which is not echoed. In response to this request, the user should supply the local system user name for identification purposes.
% ftp tragopan
Connected to tragopan.asian.pheasant.edu.
220 tragopan.asian.pheasant.edu FTP Server (Version 5.1) Ready.
Name (tragopan:wings): ANONYMOUS
331 Guest login ok, send ident as password.
Password: CARIBBEAN
230 Guest login ok, access restrictions apply.
Welcome to Compaq TCP/IP Services for OpenVMS
on internet host TRAGOPAN Date 24-JUN-2000
FTP>
|
The FTP server processes each command individually as it receives the command and displays a reply based on the command parameters. A reply can include a file specification that displays part of the server file system.
For security, anonymous FTP masks file system devices and directories in FTP replies. The following messages show the difference between an unmasked file structure, shown in the first reply, and the less-specific, masked structure in the second reply.
220 opening data connection for USER8$:[HIDEME.PROJECT.TASK]PLAN.PS 220 opening data connection for SYS$LOGIN:[PROJECT.TASK]PLAN.PS |
Complete the following steps to set up anonymous FTP access on your system:
$ DEFINE/SYSTEM/EXEC TCPIP$FTP_SERVER_ANNOUNCE - _$ "@SYS$SYSDEVICE:[TCPIP$FTP]ANNOUNCE.TXT" |
$ DEFINE/SYSTEM/EXEC TCPIP$FTP_ANONYMOUS_WELCOME - _$ "@SYS$SYSDEVICE:[TCPIP$FTP]WELCOME.TXT" |
Table 15-1 lists the logical names that you can use to manage the FTP server.
| Logical Name | Description |
|---|---|
| TCPIP$FTP_ANONYMOUS_ALIAS |
Defines an equivalence list (up to 10 entries) of the login names of
users with access to the ANONYMOUS account. These users share the same
access rights and restrictions.
If you do not define this logical name, the default is ANONYMOUS as the only login name. The following command shows how to create an equivalence list with
the names THOMAS, JONES, and SMITH. These users can log in to the
ANONYMOUS account without a password.
|
| TCPIP$FTP_SERVER_ANNOUNCE |
Defines location and file name for the announcement text displayed to
users when they connect, before the login sequence.
The following example shows a prelogin announcement:
|
| TCPIP$FTP_ANONYMOUS_WELCOME | Defines location and file name for the welcome text displayed to anonymous users at connect time, after the login sequence. |
| TCPIP$FTP_CONVERT_FILE |
Define this logical name as TRUE or FALSE. If defined as TRUE, the FTP
server converts files to variable with fixed-length control (VFC)
formatted files before transfer. With the VFC file, users retain the
Record Management Services (RMS) formatting information of their files.
For more information about RMS, refer to the OpenVMS Record Management Services Reference Manual.
If TCPIP$FTP_CONVERT_FILE is defined as FALSE, there is no conversion, and RMS formatting information is lost after the file transfer. |
| TCPIP$FTP_ANONYMOUS_DIRECTORY | Displays public directories accessible by the anonymous FTP user. |
| TCPIP$FTP_FILE_ALQ | Specifies the number of blocks to be preallocated by Record Management Services (RMS) to a disk when a file is created. |
| TCPIP$FTP_FILE_DEQ | Specifies the number of blocks to be added when RMS automatically extends the file. |
| TCPIP$FTP_ANONYMOUS_LOG | Defines the location of the anonymous log file. The default is SYS$SYSDEVICE:[TCPIP$FTP]. |
| TCPIP$FTPD_IDLETIMEOUT |
Defines the maximum time interval that FTP child processes can remain
idle before FTP closes them. TCP/IP Services terminates the FTP process
if no control or data connection activity exists for the specified
time. The default idle time is 15 minutes. This feature can help to
improve system performance.
Specify the value as hh:mm:ss. |
| TCPIP$FTP_KEEPALIVE | Detects idle and broken FTP connections. Define it on the client host as TRUE or FALSE. |
| TCPIP$FTPD_KEEPALIVE |
Detects idle and broken FTP connections. Define it on the server host
by entering:
TCPIP> SET SERVICE FTP /SOCKET_OPTIONS=KEEPALIVE |
| TCPIP$FTP_NO_VERSION |
If defined, FTP does not send file version numbers when you enter the
mget
and the
ls
commands to a host that is not an OpenVMS host. Define this logical
name in the system logical name table, as follows:
$ DEFINE /SYSTEM/EXEC TCPIP$FTP_NO_VERSION 1 |
| TCPIP$FTP_RAW_BINARY |
With this logical name turned on, FTP transfers files in block I/O mode
if the server and client are in binary (image) mode. To activate this
feature, define the logical name as TRUE.
An FTP end-user can override your FALSE definition with the FTP PUT /RAW command. |
| TCPIP$FTP_STREAMLF | If defined, the FTP server and client create files as RMS STREAM_LF files. The default is variable-length files. |
| TCPIP$FTP_WNDSIZ | Sets the size of the TCP send and receive transmission windows. Specify a decimal number for the number of bytes. |
| TCPIP$FTP_SERVER_LOG_CLIENT_BY_ADDRESS | Specifies that the FTP server will be using IP addresses instead of host names. |
| TCPIP$FTP_SERVER_NAME_SERVICE_TIMEOUT |
Specifies the number of seconds for the timeout interval. For more
information, refer to the description of the SET NAME_SERVICE/TIMEOUT
command in the Compaq TCP/IP Services for OpenVMS Management Command Reference manual.
This logical name has no effect if the FTP server is using IP addresses instead of host names (that is, the logical name TCPIP$FTP_SERVER_LOG_CLIENT_BY_ADDRESS is defined). |
| TCPIP$FTP_SERVER_NAME_SERVICE_RETRY |
Specifies the number of times the BIND resolver should attempt to
contact a BIND server if the first attempt fails.
This logical name has no effect if the FTP server is using IP addresses instead of host names (that is, the logical name TCPIP$FTP_SERVER_LOG_CLIENT_BY_ADDRESS is defined). |
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