[Info-vax] Update to TCP/IP problem with Alpha VMS 8.4

[Neil Rieck]

On Apr 4, 6:58 pm, "vmsmang... at earthlink.net"
<vmsmang... at earthlink.net> wrote:
> I am really embarassed about my original post. I know I should have
> provided a great deal more information. Since I have been working with
> and using VMS since 5.4 I know how important it is to have complete
> information. So, here goes.
>
> The Alphaserver DS20 has 1 GB memory, 1 cpu, and a mylex raid
> controller. DRA0 is the VMS 7.3.2 system disk, DRA1 is a spare disk,
> and DRA2 is a 3 member RAID 5 device with a spare drive.
>
> The Apple iMac G5 is a Power Mac with 1 GB memory.
>
> Both systems have a hosts file, TCPIP$HOST.DAT on the DS20 and etc/
> hosts on the iMac. Here is the contents of that file and is the same
> for both systems.
>
> 10.1.1.1 cougar Cougar COUGAR
> 10.1.1.3 imacg5 Imacg5 IMACG5
> 10.1.1.10 printserver Printserver PRINTSERVER
>
> Both systems and the Printserve are connected to a 5 port network
> switch. 2 printers are attached to the Printserver, a laserjet and an
> inkjet.
> Both systems can print to both printers and can also ping each other
> and the Printserver.
>
> To prepare for the 8.4 upgrade I did an image backup from DRA0: to
> DRA1:. I also did an image backup of DRA0: to mag tape.
> The intent is to Upgrade DRA0: from 7.3-2 to 8.4.
>
> This will be fairly long so I am going to break it down into several
> smaller posts.
>
> Again, my apologies to everyone who replied.
>
> Bill LaCounte, aka VMSmangler

Not sure if you are still having a problem, but remember than PING is
a low level tool which does not involve TCP or UDP. This means if you
can't "PING by ADDRESS" (pinging by name sometimes introduces other
problems like typos in your host file, DNS problems, etc.) then you
can forget about all the other stuff. At this point there are only a
few things that make any difference:

1) your IP address
2) your NET mask
3) maybe your MAC address

Going back to basics for a moment, remember that there are only a
couple of decision points here:
1) use the netmask to compare your address with the destination
address. This tells the stack if the destination is on is on your
subnet or not.
2) if the destination device is not on your subnet, then you need to
locate the nearest gateway which will handle the request for you. If
you know the address of the gateway then you will still need to use
ARP to locate the gateway's MAC address.
3) if on your subnet, then use ARP to determine the MAC address of he
destination device.
(I still remember a 5-day Synoptics class on networking back in 1992
where the instructor forced us to learn the following mantra which was
recited before every lecture: "All communications is done at the MAC
layer)

Okay so you say the Mac it working properly. Get a copy of WireShark
(replaces Ethereal) and use it to monitor the traffic between the
Alpha and the Printserver. Can you see the ARP request and response?
Can you see the MAC-to-MAC ping and response?

p.s. be sure to inspect the netmask of all devices involved.

Just my 2 cents worth :-)

Neil Rieck
Kitchener / Waterloo / Cambridge,
Ontario, Canada.
http://www3.sympatico.ca/n.rieck/