Lan Redundancy

[ardi]

Dear All,

I facing problem when i setup my network to redundant.

::::::

We have an small network - 1 win2k3 servers, and 4 XP nodes.
All nodes have 2 NIC Card one connect to CISCO Switch A, and another
to CISCO switch B,
also SERVER have 2 NIC connect to each CISCO Switch.
I also make loop between CISCO Switch A and B, so we can access server
from CISCO A or B.
...
For Win2k3 server,
We only setting the Ip addresses on static address, we don't have any
DNS, WINS, and DHCP
The Server have addresses are 192.168.0.8 and LAN B 192.168.0.18. And
one of XP node addresses are
192.168.0.11 and Node Lan B 192.168.0.21,
.......
The problem is,
when we disconnect LAN A from one XP node or turn off first Cisco
Switch we can ping the server from XP node with no delay , but when we
disconnect another LAN (LAN B) (LAN A Still connected) we got delay
about 1 minutes delay after that we could get reply from server.

.... I dont have knowledge about cisco switch. should we manage cisco
switch ??
What we must to do??

ANY thoughts advice or suggestions VERY welcome!!


Thanks.

 

[Andrew McLaren]

We have an small network - 1 win2k3 servers, and 4 XP nodes.
All nodes have 2 NIC Card one connect to CISCO Switch A, and another
to CISCO switch B,
also SERVER have 2 NIC connect to each CISCO Switch.
I also make loop between CISCO Switch A and B, so we can access server
from CISCO A or B.

Hi Ardi

What do you hope to achieve, by having all machines connected to 2 switches?

In most cases this will not provide any advantages. And as you have
seen, multihomed machines will greatly increase the complexity of the
network and make configuration difficult.

Unless you have a very specific goal, your best solution may be to
simplify the network and only have a single network connection from each
machine, all going back to a single switch.

Regards

Andrew

 

[ardi]

Dear Andrew,

I set up this network as per request from my customer to build
redundancy system. Redundant means if one line/network fail we can
use another line/network, so no data loss happening.
In this system we build redundacy for Lan/Network and redudancy for
server. so we need 2 server and 2 Cisco Switch, and also need 2 NIC
card on each Node/ server.


Do you have any suggestion to build this redudancy system ??

Regards


ardi

 

[Andrew McLaren]

I set up this network as per request from my customer to build
redundancy system. Redundant means if one line/network fail we can
use another line/network, so no data loss happening.
In this system we build redundacy for Lan/Network and redudancy for
server. so we need 2 server and 2 Cisco Switch, and also need 2 NIC
card on each Node/ server.

Selamat, Ardi

Ah, I see. You gave the customer what they asked for. That will usually
result in a bad design )

When Switch 1 goes down, the workstation does not get notified of this
immediately. It will keep using its existing arp table to contact the
server, until the failed path times out, and the TCP/IP stack switches
to the next available path. In your case this seems to take about 1
minute. That's not bad! I'm not sure you will get better results than this.

You can see the arp table for the current configuration by entering "arp
-a" at a command prompt.

There may be some tweaks to shorten the arp timeout, but I can't think
of any right now. In any case, that may have unintended side effects for
other network behaviour.

What does the customer fear most? Dead network cards, or dead switches?
If they are worried about network cards dying, then you could try using
"teaming NICs" instead - 2 network cards which share the same MAC
address. These are usually a server feature however, and are quite
expensive. For redundant switches on the same Ethernet segment .. gee, I
don't know. It's not a very common scenario. Is this a specialised
environment, such as an industrial or military application? Or, they
just want a very reliable office network?

That may not be much help for you, but it is the best I can think of
right now.

Cheers
Andrew