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Old 09-12-2009, 01:32 AM   #1
evil_empire
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modem to router to switch to PCs


Heres my setup,
Fiber optic connection(Media Converter)==> Linksys Router ==> LinkSys switch(48 ports)===>PC1, PC2, PC3....PC15

The Switch has been configured to use Routers IP as the gateway. Some computers get connection, others can't get the IP. Sometime it works when the Switch is rebooted. Sometimes, some computer work, others fail. The router has Static IP from the ISP.

What could be wrong? Whats the proper way to connect?
Is it because DHCP is working on both the switch and the router and they're configured on the same subnet?

Please help.
 
Old 09-12-2009, 01:46 AM   #2
linuxlover.chaitanya
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I am not sure how effective can be a setup with two dhcp servers in a same subnet. You could definitely try to disable one dhcp server and find out if that works.
Not getting internet could be issue with either ip configuration or gateway.
 
Old 09-12-2009, 01:51 AM   #3
lutusp
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Quote:
Originally Posted by evil_empire View Post
Heres my setup,
Fiber optic connection(Media Converter)==> Linksys Router ==> LinkSys switch(48 ports)===>PC1, PC2, PC3....PC15

The Switch has been configured to use Routers IP as the gateway. Some computers get connection, others can't get the IP. Sometime it works when the Switch is rebooted. Sometimes, some computer work, others fail. The router has Static IP from the ISP.

What could be wrong? Whats the proper way to connect?
Is it because DHCP is working on both the switch and the router and they're configured on the same subnet?

Please help.
It's generally a bad idea to have two DHCP servers running, and if they're providing addresses in the same address range on the same subnet, it's unworkable.

The problem is that you can't be sure which DHCP server will respond, and if they are in different locations in your network topology, and have different settings, it will be a coin toss whether a particular machine will be configured properly. So ... run only one DHCP server. Disable the other one.

Make sure the router with the static IP also has a valid list of name servers. Think about what information DHCP provides, and provide it all in the static configuration.
 
Old 09-12-2009, 02:01 AM   #4
acid_kewpie
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is it becuase of two DHCP servers? Well do clients have "bad" routing tables for what you want?? That would be a pretty obvious way to tell. why is the swiitch doing anything interesting at all? Is it routing?? You suggest it is, mentioning it's default route. If your route is suitable, the switch should really do NOTHING whatsoever, apart from Layer 2 switching - the dummber the better.
 
Old 09-12-2009, 02:21 AM   #5
evil_empire
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hi acid,
Since the router has only 4 ports, I hooked up the switch, the switch has 48 ports. What would be the best setup?
 
Old 09-12-2009, 02:23 AM   #6
acid_kewpie
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as above, keep the switch very dumb, unless you do wish to move some functionality across to it. But certainly you'd not want to do any routing on it.
 
Old 09-12-2009, 03:49 AM   #7
evil_empire
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Hi Acid,
Sorry for being dumb. So what you are saying is not to configure the switch to use router as the gateway.
 
Old 09-12-2009, 04:32 AM   #8
linuxlover.chaitanya
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Exactly. Do not make switch to be dhcp server. Use the switch as unmanageable. Do not even configure it unless absolutely required. Just use it to network the systems.
 
Old 09-12-2009, 06:05 AM   #9
acid_kewpie
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Well the switch is free to have a default gateway for purposes of the switch itself going out the net or such, but a client has no business sending traffic via the switch if that switch is only going to pass it on to the router on the same network anyway.
 
  


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