aliasing ip addresses

I have a QNX system that needs to be able to respond
to two separate ip addresses.

I used the ifconfig command to produce an alias.
This seemed to work for a while. Recently the host
that it needs to talk to cannot telnet or ftp to either ip address.
The host is on the other side of a switch. I can
access the system on the other side of the switch
from a Windows 98 box but not from a VMS box or
a QNX box. I can go to another machine that is on
the same side of the switch and from there telnet
to the box.

When I disable the alias, the host can talk to the single
IP address.

I have no clue how aliases work internally or how the
network configuration may affect or be affected by aliases.
Is there something that I can look at either on my QNX
system or on the host? Can someone explain how aliases
are implemented or point me to something that explains them?

Thanks,
Carlos

Ping.

On Fri, 09 Jan 2004 13:39:17 -0500, Carlos Clarke
<carlos@ptdprolog.net> wrote:

I have a QNX system that needs to be able to respond
to two separate ip addresses.

I used the ifconfig command to produce an alias.
This seemed to work for a while. Recently the host
that it needs to talk to cannot telnet or ftp to either ip address.
The host is on the other side of a switch. I can
access the system on the other side of the switch
from a Windows 98 box but not from a VMS box or
a QNX box. I can go to another machine that is on
the same side of the switch and from there telnet
to the box.

When I disable the alias, the host can talk to the single
IP address.

I have no clue how aliases work internally or how the
network configuration may affect or be affected by aliases.
Is there something that I can look at either on my QNX
system or on the host? Can someone explain how aliases
are implemented or point me to something that explains them?

Thanks,
Carlos