Re: TCP/IP connection problem

From: Dirk Munk (munk_at_home.nl)
Date: 09/25/04 

Date: Sat, 25 Sep 2004 00:33:13 +0200

Hi,

Thank you very much for your reply, but I was also replying to the original
poster RT Carter.

 From his posting I assume it is not a routing problem (since he writes that
"there are no managed hubs between the server and the workstions", most likely
that includes routers) but a mask problem. Older UCX versions can not be
configured with supernetting masks, and it that case it is not possible to solve
the problem. There is a dirty workaround, and that is to configure two IP
addresses on the same ethernet port.

Regards,

Dirk

Himanshu wrote:
> Hi Dirk,
>
> I think DOC is correct in the previous reply, I would try to elaborate
> what DOC
> tried to make you understand.
>
> Since your workstations have changed IP addresses, which could not
> have been
> known by VMS servers, there are some changes which ought to be done on
> the
> VMS servers. These changes depend upon what type network connectivity
> software you are using like UCX or multinet etc.
>
> Problem may lie in the routing options of VMS systems where the new IP
> addresses
> have to be redifined.
>
> Regards,
>
>
>
>
>
>
>
>
> Dirk Munk <munk@home.nl> wrote in message news:<cj0krt$6rp$1@news2.zwoll1.ov.home.nl>...
>
>>RT Carter wrote:
>>
>>>I do not know VMS but I am a Network Admin (Microsoft & Novell). We
>>>moved our workstations to a different building and they are now on a
>>>different network (was 192.255.1.xxx now 192.255.2.xxx)There are no
>>>managed hubs between the server (192.255.1.203) and the workstations.
>>
>>Does this mean you do not have routers between network 192.255.1.0 and network
>>192.255.2.0 ? If both network addresses are true old style class-C networks,
>>then they should have mask 255.255.255.0 . And in that case there should be a
>>router between both networks. In this situation it is likely that the gateway
>>entry of the VMS system has not been properly setup.
>>
>>Otherwise you are using supernetting, which is also known as Classless
>>Interdomain Routing (CIDR), and you will be using a mask like 255.255.254.0. In
>>fact you will not have two networks, but only one (192.255.1.0) with mask
>>255.255.254.0. If this is the case, then the mask on the VMS system is not
>>correct. It all depends on the TCP/IP software on the VMS system if a CIDR mask
>>can be set. Older versions of UCX could not be setup with CIDR masks.
>>
>>Furthermore I'm quite sure these IP address ranges have not been officially
>>registered to your company. You should be using a free range of IP addresses,
>>like 192.168.x.x, 172.16.x.x. or 10.x.x.x . In the present situation your
>>workstations will not be able to reach any systems on the internet that have a
>>address in the range of 192.255.1.0 and 192.155.2.0 (assuming they are connected
>>to the internet by means of a NAT router & firewall).
>>
>>If you would change your network addresses, use the class-A 10.x.x.x or class-B
>>172.16.x.x. addresses. With those ranges you can use subnetting which is usually
>>allowed on all older TCP/IP stacks (contrary to supernetting).
>>
>>
>>>The workstations can not ping the VMS server. They can ping all other
>>>192.255.1.xxx servers and workstations so the only problem is access
>>>to the VMS server TCPIP address. Is there some security setting that
>>>would refuse requests from the different network?

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