(Note this is a guest post by Antoni Sawicki aka Tenox)

Enter 1988… around that time Microsoft just released MS-DOS 4.01 and IBM shipped OS/2 1.1. Compare to the other two, this QNX was years ahead of its time. Pretty much on every aspect. Now, some 25 years later QNX2 is still found running industrial machinery, clean rooms, avionics and military hardware. Some people report systems up and running non-stop for 15 years and longer!

WinWorld from the past, to the present, for the future. WinWorld is an online museum dedicated to the preservation and sharing of vintage, abandoned, and pre-release software. We offer information, media and downloads for a wide variety of computers and operating systems. The file you specify doesn't have to be a CD-ROM block special file. For example, it could be a regular file that's an image of a CD-ROM or it could be a WORM drive containing an ISO 9660 filesystem. Description: The Iso9660fsys filesystem manager provides transparent access to ISO 9660 filesystems. It supports Rock Ridge Interchange Protocol. For directory=file, you should also note that the specified file needn't be an actual CD-ROM as long as it contains an ISO 9660 filesystem. Information directory. A directory called.cd.information. Is always created beneath the directory of the mounted ISO filesystem (e.g. /cd0/.cd.information.Another directory may also be created if a valid volume ID is present on that filesystem. FreyrSCADA offering IEC101 RTU Server Simulator IEC101 Client Master Simulator, Static and Dynamic Libraries, Source Code Library. Driver for Windows, POSIX Linux, ARM, PowerPC, QNX & more. Make your RTU, protocol converter, Gateway, HMI, Data concentrator compatible with iec 101. Download Free Evaluation Kit - IEC 60870-5-101 Development. Mount the QNX 4 partition found on the second hard disk as the user directory: mount /dev/hd1t77 /home. Mount the ISO 9660 filesystem present on the CD-ROM device /dev/cd0 as /cd0: mount -t iso9660 /dev/cd0 /cd0. Note that in the above case, mount would invoke the following utility: mountiso9660 /dev/cd0 /cd0 Exit status: 0 Successful.

It took me similar amount of time to acquire usable media set. QNX is an embedded system and never really seen life on a desktop machine, so finding these floppies was rather hard and expensive adventure. Fortunately I can finally let it see some daylight. Let’s examine how the system will install on a modern hardware under VMware Workstation.

From a native QNX system go to /boot/build; Build a default OS image: mkifs bios.build bios.ifs; Create a partition on the card or USB stick if there isn't one yet like this: # fdisk /dev/ Create a partition of type 77,78 or 79 and make it bootable. I've just tried to launch QNX 4.25 ISO bootdisk on qemu-system-x8664 built from current git. QEMU screen is skewed (see on screenshot). I tried all different options in -vga key - all the same. Lukas Jirkovsky (l-jirkovsky) wrote on 2018-03-23: #11: This is still a problem with QEMU 2.11.

The install is rather straight forward. Floppy boot comes with a login prompt.

After you log in as qnx you need to swap the floppy disk to Boot Utilities and run install. The script guides you through setup steps.

First you need to select the disk controller. For compatibility mode QNX 2 provides access via int 13 (real mode).

Then you partition the disk. QNX partition type is either 7, 8 or 9. You will be asked to mark it bootable later on.

Then you have to select the kernel. QNX can operate in real mode and protected mode on AT286.

The install script copies all the data from distribution floppy disks, asks about boot loader and active partition. Finally you get to choose some video options.

The system also asks about networking options. Unfortunately it only works with custom Arcnet cards so I skipped this. Once complete you are asked to remove the boot floppy disk and reboot the machine. This is what comes up after first hard disk boot.

I guess what is in the system will be the a topic of another post.

QNX 2.x files are here, a ready to run VMware image is here. Virtual Box here.

Updates:
You may also be be interested in QNX Windows and Fun with QNX 4 Networking posts.

This chapter covers the following topics:

Before you begin...

In the next three chapters, you'll learn about configuring basic TCP/IP clients,servers, and gateways. But before you begin configuration,you should plan the basic layout of your network (seeprevious chapter); you should also address the followingissues (chapters indicated are from the 2nd edition of TCP/IP NetworkAdministration):

Please also note that if you:

• wish to successfully run most of the programs described in this chapter, you should be logged in as the superuser(root).
• would like to read online discussions about QNX TCP/IP,you should join the quics.experts.tcpipnewsgroup on QUICS. With theappropriate service plan, you can also post technicalquestions to the newsgroup. For information on using QUICSand getting the latest software updates, see the QNXInstallation & Configuration guide.

The QNX approach

In QNX, the distinction between ``system' and``user' processes is practically nonexistent.Some processes are called managers (ordaemons in Unix terminology), but that's simplybecause they manage a specific resource and provide aservice to other processes.

To configure a computer in QNX, you have to start severalprocesses. Which processes you start depends on the servicesyou want that computer to provide. By adding the appropriateprocesses to a computer's startup script file (e.g.sysinit.node), you can easilyenable a computer to be a QNX workstation, a TCP/IP client,a TCP/IP server - or all three!

Shared libraries

QNX 4.25 TCP/IP uses shared libraries. The libraries are represented by thebinaries rpc_so, snmp_so, and socket_so.To run any executable (except for Socklet, Socket, and Sockppp)you must have these binaries available. They won't show up in a sin listing, but they do createentries in /dev/shmem. If you wish to remove the socket sharedlibrary (not a good idea while you're using it), use the following command:

You can remove the RPC and SNMP shared libraries in the same way.

Client vs server configurations

The minimal configuration of a TCP/IP host is that of aclient host. To transform a client into a server,you simply add the desired server daemons to thatclient's configuration.

Since client and server configurations can be performed inisolation, we describe them separately here. This structurewill help you configure any host as a client and thensubsequently add server capabilities as required.

A word about protocols

The name ``TCP/IP' implies two main protocols- TCP and IP - in a suite of many protocols.

IP is the main protocol upon which most protocols arelayered. In order to use TCP/IP you need an IP address. Younormally get your IP address from an ISP (Internet Service Provider), directly from theInterNIC, or from your MIS department.

If you're setting up a network that is separated from anyother machines, then you can use the IP address192.9.200.x, where x is anumber in the range 1 to 254. Many QNX users give thelogical node ID as the suffix for the IP address (e.g. node15 might be 192.9.200.15).

The simple way to map between alphanumeric names (e.g.qnx.com) and IP addresses is via a table keptin the /etc/hosts file. This works fine forsmall to medium networks. If you think this is gettingunwieldy for your network, then you should read the chapteron DNS (Domain Name Service) in TCP/IP Network Administration.

Note that many of the following sample configurations makesome assumptions about routing, which can bedefined as the act of choosing how to get a packet to itsdestination. See the ``Routing'section in this chapter.

Quite often the series of commands you need to start up theTCP/IP aspects of networking are gathered together in thescript /etc/netstart. The runtime productincludes an example script. Once you work out your specificneeds, you should modify that script accordingly. If youhave multiple workstations sharing /etc (viaQNX networking) and they each have different TCP/IP needs,it's customary to name the various scripts/etc/netstart.node.

If you have several TCP/IP hosts/servers on a QNX network,you can select which one you use by setting the environmentvariable SOCK to the node number of theSocket Manager you wish to use.

Logging to syslogd

Many TCP/IP programs produce logging or debugginginformation. For example, sendmail logs a messagewhenever it processes incoming or outgoing mail. Byexamining this type of information, you can verify thatlocal host programs are operating correctly.

While some programs write this type of information tostandard output or standard error, many will sendsupplementary status information to syslogd, ifit's running. In certain circumstances, logging might alsogo to the /dev/console file.

Since the /dev/console file doesn't exist ina default QNX system, you may need to execute the followingcommand:

The file argument is the device or file you wantto use as your log device. For example, if fileis /dev/con1, logging goes to console 1. Butif file is /tmp/logfile, theoutput goes to /tmp/logfile on disk.

Routing is the act of determining how to get a packet to itsintended destination.

There are really three general categories of routing:

• minimal routing - if you're isolated onyour own network (single piece of wire), then it's unlikelyyou'll need to do anything to route packets.
• static routing - if you're on a networkwith a small (and static over time) number of gateways, thenyou can use the route command to configure therouting tables within Socket and leave them thatway. This is a very common configuration.
• dynamic routing - if you're on a networkwith more then one possible route to the same destination onyour network, then you might need to use dynamic routing.This relies on routing protocols to distribute informationabout the changing state of the network. If you need toreact to these changes, then you need to runrouted or gated.

  Although gated isn't shipped with the TCP/IP implementation, you'll find a free (unsupported) version in the TCP/IP area on QUICS.

There's often confusion between routing and routingprotocols. Routing is done by Socket via routingtables; routing protocols allow those tables to change.

Utilities for debugging

Several utilities are useful for debugging TCP/IPconfigurations:

to see if you're connected to the other end of the link.

With success, ping will output something likethis:

This report will continue until ping isterminated. To terminate ping, pressCtrl-C. You'll seea report like this:

The ping utility may fail for different reasons:

• If nothing is displayed, ping may be havingproblems resolving the hostname. Try the IP address directly to bypass the resolver (see the/etc/resolv.conf file).
• If only the first line of the above successful outputis displayed, then ping isn't receiving aresponse from the specified host.
• All other problems and errors will output an obvious message (e.g. ``No route to host').

netstat and route

A common problem involves configuring a PPP interfacecorrectly. Assume that the user has established theconnection using pppd. Now the user can ping themachine he's dialed into (isp.com), but notanything past it (e.g. the Internet). The user's routingtables (from netstat -rn) look like this:

Note that the user has a route to isp.com(10.0.0.1) and to localhost. What the userreally needs is a route to ``anywhere he doesn't havein his list.' This is called the default route. It canbe automatically added via the defaultrouteoption to pppd, but can also be added later viathe route utility (e.g. route add defaultisp.com).

In other cases the need for a route isn't so obvious to see.Suppose your machine has two interfaces. Which interfacedoes a packet take? Here's the output ofnetstat -rn and netstat -inon such a machine:

What are some of the things this output tells us? The lineunder (root node) tells us that packets bound for network 10will go out the en2 interface. The line below that tells usthat packets bound for network 10.8 will go out the en9interface.

What's the difference between network 10 and network 10.8?The answer lies in the IP address and in something called anetmask. During routing, a gateway divides the address into two parts (the networkand the host) using the netmask.

The network part is used to determine how to route a packetuntil it has reached its own network, at which point thehost address is used.

To find the netmask for an interface, we need to use thecommand ifconfig en9, which gives thisoutput:

This tells us that the netmask for en9 isffff0000.

Similarly, we find that en2 has the netmask ff000000. So, how do we determine what interface apacket bound for 10.0.0.5 will take? We look down therouting table for the longest match.

If we ``bitwise and' 10.0.0.5 with the 10 netmask(255.0.0.0), we see that the network portion lines up withthe entry in the table. Thus the packet will go out theen2 interface. If we then look at a packet boundfor 10.8.0.67, we find that 10.8 is the longest match andthat we'll use en9. If we then look at a packet bound for10.2.0.5, we pick en2 since it's the longest match.

Address mapping via arp

Throughout this manual we've been working with IP addresses.But at the hardware level, networking hardware uses othertypes of addresses. For point-to-point links it's just``the other end.' For common access network medialike Ethernet, it's some other type of address (a 48-bitnumber called a MAC address). Since IP addresses are 32-bit,we can see that there must be some sort of mapping betweenIP and MAC addresses. This could be held in a database like/etc/hosts, but that would make it hard toadd a new machine to the network.

To handle address mapping, IP uses Address ResolutionProtocol (ARP). If you have an interface directly on thenetwork of the packet, then you can send out anarp request to find the full hardware address ofthat host.

If you get an answer back, then you can store that in acache and continue with your network transaction. Latercommunications will only cost you a cache lookup, not awhole network transaction. If you don't talk to a host for awhile, you can purge that entry from the cache.

If the destination isn't directly connected to your network- and you have a route to its network - then youcan look up the address of the gateway (host that relayspackets onto another network) for that destination and ARPfor it. If you get an answer back, then you can continuewith your network transaction sending the packet intendedfor the destination to the gateway instead.

This is all to introduce a simple little utility calledarp, which lets the user list and manipulate theARP cache. You can use arp to set up proxy arp,which is where you answer the ARP request for another host(possible on a SLIP or PPP link), thus providing a limitedform of routing.

You can also use arp to identify when you've gotthe wrong address for a host. Options to arp letyou list, delete, and set entries in the cache.

Both arp and netstat are fine toolsfor looking at routing on your local network, but they'renot very good for examining what's going on acrossthe network. You'll find nslookup andtraceroute useful for this.

nslookup

Qnx 4.25 Iso

The nslookup utility lets you query the DNSdatabase. For example, when you enternslookup vir.com, you'll get:

This tells us that qnx.com thinksvir.com has the address 199.84.154.69. Youcan also ask what another host thinks a third host's addressis. The command:

gives us:

This tells us that vir.com thinksneocom.com is at 165.90.128.240. We can thenask man.net where neocom.com is by entering:

This gives us:

This tells us that at least these two hosts have a commonview of where neocom.com is. This only hintsat how useful nslookup can be. The utilityallows you to find out what a certain host's MX records are,what their nameservers are, and all sorts of otherinformation.

traceroute

The traceroute utility lets you find outinformation about the route your packets take to a certainhost. The utility takes the destination host as one of itsarguments. The output of traceroute vir.comlooks like this:

So what does this tell us? To go from thecisco at qnx.com in Ottawa toZotique.Vir.com in Montreal takes 14 hops.The three times printed are for three probes sent to thatsite. An asterisk (*) is printed if the probe is lost.

If this data showed a bottleneck along the way, then itcould be used to choose a better Internet provider or tolook for a mirror of whatever service the destinationprovides.

To enable the host to act as a gateway (a machine thatforwards packets between interfaces), specify the-d forward option to Socket:

With this option, data packets will be routed from onenetwork to another. Note that each interface must resideon a different IP network.

We've covered the processes that constitute a basic clienthost. In this section, you'll learn about what's required toadd server capabilities to a client host.

Daemons

What does being a server mean? If a host is a server, itwill invoke the appropriate daemon to satisfy aclient's request. Note that most TCP/IP daemons have namesending with the letter ``d.'

A TCP/IP server typically runs the inetd daemon (also known as the ``super-server').

The inetd daemon

The inetd daemon listens on the TCP/IP network for incoming client requests. Upon receiving a request, itexecutes the corresponding server daemon. For example, if aclient requested an rlogin, then inetd wouldstart rlogind (remote login daemon) to satisfythe request. In most instances, responses to client requestsare handled this way (see TCP/IP Network Administration).

You use the /etc/inetd.conf file to specifythe daemons that inetd can start. Thedistribution contains a sample inetd.conffile that has entries for all the servers currentlysupported by TCP/IP for QNX, including these commonly useddaemons:

inetd.