ptx/SNA PU2.1 Base Server V4.7.0 Release Notes


Introduction

These release notes support Version 4.7.0 of the ptx®/SNA PU2.1 Base Server and ptx/SNA SDLC & LLCI software. Read this document before installing this software on your NUMA system.

The software installation procedure is documented in the DYNIX/ptx® and Layered Products Software Installation Release Notes. Read these release notes thoroughly before installing the ptx/SNA PU2.1 Base Server software.


Product Compatibility

The following software products are prerequisites for the ptx/SNA PU2.1 Base Server V4.7.0 software:

The following hardware products are prerequisites for ptx/SNA PU2.1 Base Server V4.7.0:


New Features in This Release

ptx/SNA PU2.1 Base Server V4.7.0 will now run in a threaded environment. However, the product does not support threaded operations.


ptx/SNA PU2.1 Base Server V4.7.0 Software

The installation CD contains the following products:

ptx/SNA SDLC & LLCI V4.7.0

ptx/SNA PU21 Server V4.7.0


Software Installation

Read the "Problem Report Summary" before installing the software.

ptx/SNA PU2.1 Base Server is a layered software product. Layered product installations are described in the DYNIX/ptx and Layered Products Software Installation Release Notes. Perform all of the necessary steps in these release notes and also do the following steps when you install the software packages:

  1. Select the ptx/SNA SDLC & LLCI product. The package name for this software is "BrxKernel".

  2. Select the ptx/SNA PU2.1 Base Server software. The package name for this software is BrxPU21.

  3. Because the BrxKernel product contains STREAMS drivers and modules for SDLC & LLCI and also declares kernel parameters, you must recompile the kernel after installing the software.


    ATTENTION

    You can choose to recompile the kernel after installing all other products, including any other product from the ptx/SNA V4.7.0 product set (for example, ptx/SNA LU6.2 (APPC) V4.7.0).

    Proceed to the "Kernel Configuration for ptx/SNA V4.7.0 Products" section later in these release notes for information on which kernel parameters to change before compiling a kernel. Most of these changes are based on the size of the ptx/SNA configurations you plan to run (such as number of links, PUs, LUs, or LU types).


  4. Set up to use SDLC with ptx/SNA V4.7.0.

    One of the components of SDLC is a packet-level driver that runs on the SBE PCI-360 Intelligent High-Speed Synchronous Serial Communications Adapter (SYNC board, NUMA systems). This packet-level driver must be loaded on each board that will be used to connect when using ptx/SNA V4.7.0 over SDLC to an IBM mainframe, AS/400, or another SNA system. The packet driver should be set up according to the following procedure:

    1. At the system prompt, type menu.

    2. Choose Network Administration from the ptx/ADMIN® menu.

    3. Choose Sync Setup from the Network Administration menu.

    4. On NUMA systems, select Add a Board from the Sync Setup menu.

    5. Provide the appropriate input as follows:

      On NUMA systems

      Enter the board number in the Enter Board Number field.

      Enter the quad number in the Quad Number field.

      Enter sdlc or both in the Enter Software field.

    6. Execute the form by using Run or pressing Ctrl-F.

      This will create a script called /etc/rc2.d/S43syncx on NUMA systems in which x is a board number. This script automatically loads the board-level packet driver, if you do not plan to reboot from the script with the start parameter (for example, /etc/rc2.d/S43syncx start).

  5. Reboot the operating system.

    This step makes the SDLC and LLCI STREAMS driver and modules available for ptx/SNA V4.7.0 applications.

    You may want to reboot after you have installed all ptx/SNA V4.7.0 applications and any other products that you are planning to install.

Table 1 lists all of the package names and the corresponding directories and files.

Table 1. Directories and Files for the ptx/SNA PU2.1 Base Server

Application

Package Name

Directory/Files

ptx/SNA SDLC & LLCI

BrxKernel

/usr/conf/uts/io/brixton/*/*

/usr/conf/uts/symmetry/brxsna.std

/usr/conf/uts/symmetry/brxsna.mod

/usr/conf/uts/symmetry/brxsna_std.a

/dev/MAKEDEV.brxsna

/usr/local/brixton/sdlc/*

ptx/SNA PU21 Server

BrxPU21

/usr/local/brixton/BrxPU21/*

/usr/local/brixton/BMD/BCFG_msglib

/usr/local/brixton/BMD/BMSG_msglib

/usr/local/brixton/BMD/BSCA_msglib

/usr/local/brixton/BMD/CSRV_msglib

/usr/local/brixton/BMD/OP20_msglib

/usr/local/brixton/BMD/PU21_msglib

/usr/local/brixton/BMD/PUNS_msglib

/usr/local/brixton/BMD/QLLC_msglib

/usr/local/brixton/BMD/SNAS_msglib


The installation procedure is now complete.


Kernel Configuration for ptx/SNA V4.7.0 Products

To use the ptx/SNA V4.7.0 software, you may need to adjust three types of kernel parameters and then recompile and reboot. The three types of kernel parameters are TCP/IP parameters, general kernel parameters, and STREAMS buffers. Each is described in the following subsections.

To change kernel parameters, perform the following steps:

  1. From the ptx/ADMIN menu, select System Administration (A).

  2. Select Kernel Configuration (C).

  3. Select Configure (k).

  4. Select your current kernel version and modify the Visibility level for parameter changes to specify that you want to see All options, (A).

  5. Select Run (Ctrl-F or PF1)


TCP/IP Parameters

The ptx/SNA V4.7.0 applications use internet sockets (TCP/IP) for interprocess communication. All clients of the ptx/SNA PU21 server (such as 3270, LU6.2, 3770, and the TN3270 servers) talk to the server over TCP/IP sockets. Similarly, all clients of the ptx/SNA LU62 server (such as 5250 and APPC applications) talk to the server by using TCP/IP sockets. Also, EHLLAPI programs talk to the 3270 terminal emulation process by using TCP/IP sockets.

Table 2 defines the client/server relationship.

Table 2. Client/Server Relationship Table

Server

Client

TCP (Socket) Connections

ptx/SNA PU2.1

LU6.2 Server

2 per LU Type-6.-2

3270 applications (brx3270tty, brx3270x, brx3287)

2 per LU Type-2, -3

TN3270 Server

2 per LU Type-2, -3

3770 (RJE)

2 per LU Type-1

brxop (Operator)

2 per brxop invocation + 2 listeners

ptx/SNA LU6.2

APPC application 5250

Min: 2 per LU Type-6.2

Max: 2 per session (independent LUs) + 1 listener

ptx/SNA TN3270

TN3270 client (brxtn3270tty, brxtn3270x)

2 per LU + 1 listener

brx3270tty, brx3270x,

EHLLAPI application

2 per LU + 1 listener

brxtn3270tty, brxtn3270x

EHLLAPI application

2 per LU + 1 listener



NSOCKET (number of TCP socket connections available)

If the number of concurrent sockets available for NSOCKET are not already set high enough, you should increase that amount. To make an estimate, look at all the configuration files for ptx/SNA V4.7.0 that will be concurrently active at any given time. Use the table above to make an estimate based on LU type and the number of applications that may be active at the same time. Add an extra amount for times of peak usage. The concurrent number of connections needed may be smaller than the maximum needed because all LUs may not be active (that is, have clients active on them) at the same time. However, LU Type-6.2 as a client of PU2.1 will bring up all of the LU Type-6.2s when ptx/SNA LU6.2 is started up by PU2.1.

The following kernel parameters should also be increased if the NSOCKET parameter has been adjusted:

N_DEV_TCP (the number of STREAMS opens of /dev/tcp allowed)

N_DEV_UDP (the number of STREAMS opens of /dev/udp allowed)


TCP_KEEPINIT (seconds before giving up on connection request)

Each ptx/SNA V4.7.0 application that is a client of a server (refer to the above table of client/server relationships) establishes a socket connection (TCP/IP) upon starting up. If you expect a lot of clients of the ptx/SNA PU2.1 server (such as the ptx/SNA LU6.2, RJE (3770), 3270, or TN3270 servers) to start concurrently, set TCP_KEEPINIT to 0 to avoid connection timeouts (failure to establish connections).

Usually it is good to specify 0 for TCP_KEEPINIT when you have a lot of LU Type-6.2s in your configurations (that is, more than 32). The ptx/SNA LU6.2 server establishes a connection for each LU as soon as the ptx/SNA LU6.2 server starts.

A good starting place is to set TCP_KEEPINIT to 0 unless there are specific reasons not to do so.


General Kernel Parameters


SFNOLIM and HFNOLIM (max number of file descriptor per process)

Each side of a socket connection is a file descriptor. Applying Table 2 to your configuration, estimate the need of file descriptors for the ptx/SNA LU6.2 and ptx/SNA PU2.1 server. Set the amount to the largest value expected.

A good starting estimate is four times the maximum number of LU Type-6.2s that are expected to be active concurrently.


NPROC (max number of concurrent processes)

In most kernel configurations, this value will already be set high enough not to need any adjusting. However, you can update it by basing your estimate on the expected number of additional processes to be concurrently active when you are using the ptx/SNA V4.7.0 products.

Refer to Table 3 when planning the number of processes for the products that you intend to use.

Table 3. Processes Per Product

Product

Processes

ptx/SNA PU2.1 Base Server

1 per active configuration

ptx/SNA LU6.2 Server

1 per active configuration with Type-6.2 LUs

ptx/SNA APPC

1-2 per invocation

ptx/SNA 3270 (brx3270tty, brx3270x, brx3287)

1 per invocation

ptx/SNA EHLLAPI

1 per invocation

ptx/SNA TN3270 Server

1 + (1 per TN3270 client invocation)

ptx/SNA TN3270 (brxtn3270tty, brxtn3270x, brxtelnet)

1 per invocation


If NOFILETAB is no longer defaulted to NPROC, it may also need to be updated based upon the number of additional processes expected to be concurrently active when you are using the ptx/SNA V4.7.0 products.


STREAMS Buffers

STREAMS buffers are used by SDLC and LLCI components in the kernel. Determine the size of the STREAMS buffers that need to be adjusted (for example, NBLK128, NBLK512) and the number of buffers for each of these sizes.

To determine the size of the STREAMS buffers, look at MAXDATA (located in configuration files such as brxpu2.config) for all DLC directives in all the configurations expected to be active for ptx/SNA V4.7.0 products.

SDLC and LLCI use the following:

The size adjustment of each STREAMS buffer depends on the activity on each of the DLCs (Physical Units in SNA terms).

A good start is to adjust each of the NBLK<x> determined above by 10 times the MODULO in the corresponding DLC directive (8 is the default MODULO for SDLC PUs, and 128 is the default MODULO for token-ring PUs).

Adjust the NBLK128 by the total number of buffers adjusted across the various NBLK<x>. That is, if NBLK512 was adjusted by 100 and NBLK2048 was adjusted by 50, adjust NBLK128 by 150 (100 + 50).

Note that STREAMS buffers will also be used when you are using sockets for interprocess communication. However, the number needed for sockets interprocess communication should already be adjusted - based on the adjustment to N_TCP_PCB_FREE.

If this estimate proves to be insufficient, use strstat to determine which sizes of buffer allocations are failing the most and adjust accordingly.

Your goal is to configure the STREAMS buffers so that the system will experience no failures or, at worst, very infrequent failures. To achieve this goal may require a few iterations.


ptx/SNA-Specific Configuration

ptx/SNA V4.7.0 allows you to restrict the number of SDLC and LLC-related resources. Proceed through the ptx/ADMIN system as described in the steps provided earlier (at the section entitled " Kernel Configuration for ptx/SNA V4.7.0 Products" ).

To preconfigure the maximum number of SCC-V boards, select BRXSDLC_BRDS and specify a value in the range of 1-8 (the default is 8).

To preconfigure the maximum number of SNA PUs (DLC directives) for SDLC lines, select BRXSDLC_PUS and specify a value in the range of 1-64 (the default is 16).

To preconfigure the maximum number of SNA PUs (DLC directives) for token-ring lines, select BRXLLCI_PUS and specify a value in the range of 1-64 (the default is 16). Note that 16 PUs is the currently supported maximum number of PUs for SDLC or token ring. This number of PUs also applies if SDLC and token ring are used at on the same network.

To preconfigure the maximum number of ptx/SNA PU2.1 servers that can use SDLC, select BRXSDLC_SRVS and specify a value in the range of 1-64 (the default is 8).

To preconfigure the maximum number of ptx/SNA PU2.1 servers that can use token ring, select BRXLLCI_SRVS and specify a value in the range of 1-64 (the default is 8). Note that 8 servers is the currently supported maximum for SDLC or token ring (or if both are used at on the same network).


Before Starting the PU2.1 Server

Each ptx/SNA PU2.1 server starts a particular SNA configuration specified by the -f switch. If the configuration contains Type-6.2 LUs, the LU6.2 server is also started by PU2.1.

An SNA configuration file contains specifications for the following:


ATTENTION

1) When creating token ring configurations that contain multiple PUs, remember that only one DLC may be defined for each TRLINE directive. In other words, each remote location should have its own TRLINE/DLC set of directives.

2) Do not modify the ACTIVITY_TIMEOUT (located in configuration files such as brxpu2.config) keyword on the DLC directive for SDLC Links. Lowering this value below the default of 20 seconds could cause Frame Reject (FRMR) problems.

3) Verify that the PAUSE (located in configuration files such as brxpu2.config) keyword on the SDLCLINE directive is set to zero.


Make sure that the kernel has been configured, compiled, and rebooted as discussed in the previous sections.

Make sure to obtain from Customer Support an Encoded Option String (EOS) that is valid for your DYNIX/ptx system.

Make sure to start the PU2.1 server with the -F <max open file descriptors> switch so that if the ptx/SNA PU2.1 server and the LU6.2 server are started, they will have enough open file descriptors to accept client connections.

Only the superuser can invoke the ptx/SNA PU2.1 server, the ptx/SNA LU6.2 server and brxop (operator interface). Make sure that the following are in the PATH of the superuser:

Only the superuser can issue the kill command from the brxop operator interface.

For other options when starting the ptx/SNA PU2.1 server, refer to the ptx/SNA PU2.1 Base Server Administration Guide.


Recommended Configuration for Running 1024 3270 Sessions

Use the following configuration for running 1024 3270 sessions:

On NUMA systems


Starting Multiple PU2.1 Servers

The ptx/SNA V4.7.0 product allows multiple ptx/SNA PU2.1 servers to be active on the same system. Each ptx/SNA PU2.1 server must execute with a different configuration. Each will have its own ptx/SNA LU6.2 server also, if the configuration contains LU Type-6.2s.

By default, the ptx/SNA PU2.1 server listens for client connection requests on the brx_pu2_espd service name specified in the /etc/services file:

brx_pu2_espd    5020/tcp

The ptx/SNA PU2.1 server also listens for brxop (operator) requests on the brxadmin_pu2 service name specified in the /etc/services file:

brxadmin_pu2    5021/tcp

These entries are made in the /etc/services file when the ptx/SNA PU2.1 Base Server product is installed.

Similarly, by default, the ptx/SNA LU6.2 server listens to its client connection requests on the brxlu62_serv service name specified in the /etc/services file:

brxlu62_serv   5019/tcp

This entry is made in the /etc/services file when the ptx/SNA LU6.2 Server product is installed from the tape.

The SERVICES directive in a configuration can specify an explicit service name for the following:

If you start more than one ptx/SNA PU2.1 server on a platform, make sure of the following:

When invoked, the ptx/SNA PU2.1 and ptx/SNA LU6.2 clients (refer to Table 2) will listen for client connections to the service names mentioned above. Each client supports a special switch for specifying the appropriate service name (for example, -z <service name> for brx3270tty) to connect to a specified PU2.1 or LU6.2. Refer to the individual product documentation for details.

This feature allows DYNIX/ptx multiprocessor systems to perform better with improved static-load balancing for clients and servers.

The following example is for a configuration file:

SERVICES  PU2_ESPD=brxserv2
          PU2_ADMIN=brxadmin2
          LU62_SERV=brxlu6212

The following example is for a /etc/services file:

brxserv2    6020/tcp
brxadmin2   6021/tcp
brxlu6212   6022/tcp

brx3270tty -z brxserv2


Related Documentation

The documentation set consists of the following manuals:


Problems Fixed in This Release

The following problems were fixed in this release of ptx/SNA PU2.1 Base Server.

242040 - brxpu2.1 Dumps Core after Specifying NWUSID Inside the Configuration File

241977 - Dates Generated by brxop Are Still Wrong

240950 - QLLC Configurations Do Not Reject PU2.1 Configurations


Open Problem Reports


Problems with kill -9 on Multiple Servers (233426)

Do not use the UNIX® shell command kill -9 to terminate multiple servers concurrently because you can panic the system.

Workaround: You can shut down multiple ptx/SNA PU2.1 servers by using the brxop utility's kill command, as is shown in the following example:

% brxop -z admin_port
> kill

This process should be repeated for each server.


SDLC Frame Rejects Are Issued Erroneously (211192)

An ACTIVITY_TIMEOUT that is smaller than the default (20 seconds) can cause SDLC to issue frame rejects (FRMRs).

Workaround: Use the default ACTIVITY_TIMEOUT in the configuration files.


SDLC Lines Can Be Dropped (2112265)

In some situations when multiple servers are on the same machine, SDLC lines that are associated with servers other than the one being terminated (using kill from brxop) can also drop.

Workaround: Use PAUSE=0 in the SDLCLINE directive in all configurations.


PUs Go into Pending Contacted (211902)

Physical Units (PUs) go into " pending contacted" state when the system is running a very high stress load. This problem is caused when there are many STREAMS buffer failures.

Workaround: Configure more STREAMS buffers of the sizes that are failing; then recompile the kernel and reboot.


brxop stats Command Is Not Supported for Token Ring (210097)

The stats command on token-ring links is not supported. If you are using token-ring links and issue a stats command, the brxop process will hang. The brxop process must then be killed (use Crtl-C).

Workaround: None.


Device Configuration - Additional Information

When you install the BrxKernel package, the SDLC devices are created automatically, because the installation includes the following command:

# /dev/MAKEDEV.brxsna brxsdlc

This creates the following devices:

When installing the ptx/LAN product, the token-ring devices are created as /dev/net/tr<x> where x is the board number.

One of these device names has to be specified in the TRLINE directive - based on the token-ring (tr) board used. Refer to the ptx/SNA PU2.1 Base Server Administration Guide.