Re: Catalyst 1900 Configuration {lost} sorry

On 20 Apr, 14:50, the....@xxxxxxxxx wrote:
Welp, I think I almost have it!  Here is where I am right now....
Basically, I have two Windows machines tied into this Catalyst 1900.

Machine #1

----------

IP Address: 192.168.1.8

Subnet Mask: 255.255.255.0

Default Gateway: 192.1.1.90

Machine #2

----------

IP Address: 192.168.1.9

Subnet Mask: 255.255.255.0

Default Gateway: 192.1.1.90

Catalyst 1900

-------------

The Cisco unit was reset to default "factory" settings.

Machine #1 is plugged into PORT 1, and Machine #2 into PORT 2.

In the PORT 1 addressing area of the Console menu, I have listed the
Physical Address 00-2A-23-E1-EB-19 of Machine #1 as the Accepted
Source Port and it is the only PA listed

For PORT 2 I did the same, listed the Physical Address of Machine #2
00-3D-31-E0-EE-22 as the Accepted Source Port.

Problem is.... when I ping Machine #2 from #1, it does not respond.
However, from Machine #2, I can ping #1 and itself (#2)... so that
seems cool.  I don't understand why I cannot ping Machine #2 from #1.
Any clues? :-) Would it be something I am probably not setting up
right on the machine, or maybe something I am missing in the Switch
configuration?  I am still slightly confused on the setup procedure.

Thank you in advance for insights & please have a great day!

Sarah.

The two machines should communicate without ANY
configuration of the switch. The correct name for the function
of a switch is "transparent bridge" but the marketing boys
and girls got their hands on it and we are now stuck
with switch.

As its name suggests a transparent bridge is not visible
to the end systems.

Most switches including your one, work right-out-of-the-box.

I do not know the terms you refered to "Accepted
Source Port" (the 1900 is very old
and it is a while since I have seen one) and I cannot find
them on CCO.

Back to your "problem" of one machine being able to ping the
other and not vice versa.

This could be caused by one of the machines being configured with
a firewall.

If ping is working one way in such a simple set-up then
nearly everything is in place for it to work the other way too.

Ping from A to B needs.

1.
machine A to be able to ARP for machine B
MAC broadcast to reach machine B
MAC unicast to be able to machine A
2.
source m/c ping request packet to reach ping machine B
MAC unicast to reach machine B
3.
target m/c to be able to ARP for machine A
MAC broadcast to reach machine A
MAC unicast to be able to return
4.
machine B ping reply packet to reach machine A
MAC unicast

If any one of these is broken then ping will not work.

You can verify arp on most hosts with

arp -a

Windows, Linux ...


H:\>arp -a

Interface: 192.168.7.176 --- 0x7
Internet Address Physical Address Type
192.168.7.1 00-50-00-5e-53-68 dynamic
192.168.7.12 00-50-00-fb-71-44 dynamic
192.168.7.14 00-50-00-c1-80-42 dynamic


In the non working direction you could clear the ARP
tables (often arp -d) and do the ping.
Then check the ARP tables on the two ends. This may
tell you how the ping is progressing.

The other essential tool is a packet sniffer such as Wireshark.
Freeware and pretty nice.

Oh, I suppose you should set your PCs to Auto Speed/Duplex.
This is unlikely to be affecting your test but it is possible
that it is if there is other traffic.

.

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