UK BOINC Team Forum

ok i have a 24 port TPlink gigabit switch and an 8 port gigabit no name switch. i have moved my i7 system in with the i3 system. the i3 was hardwired to the network with a 10m cat5e that i took the time to route under carpet so it wouldn't show. This 10m cable is connected to the 24 port switch and works great. now if I take this 10m cable and plug it into one of the ports on the 8port switch and then connect both the i7 system and the i3 system to the switch as well both computers will light up the switch green showing 1GBps but dhcp will not assign an IP address so i have no access to internet. I get an error that “Ethernet“ doesn’t have a valid ip configuration
Anyone have any ideas, as i thought this was just a plug and play scenario

Thanks

Neil

Ok after setting properties of ipv4 to static ip adress192.168.1.250 and 251 subnet 255.255.255.0 default gateway 192.168.1.1 I am getting a default gateway not found

Curiouser and curiouser said Alice

Hi Neil

It might be an idea if you can "draw" the layout of the network cabling, along the lines of:
Also check that both switches are "dumb" and do not actually have their own network config/admin sections.

regards
Tim

Its funny you should mention this as i'm just about to buy a couple of switches for the server and other stuff. It was my understanding that you could just daisy chain them from the router, attaching pcs off each switch and all would work normally? As in Tim's diagram.

Am I right in thinking this will only work with unmanaged switches eg plug and play?
Is a 'dumb setting' the same as unmanaged?

If a single switch doesn’t have enough ports for your entire network, you can connect switches together by daisy-chaining them. On older switches, you sometimes had to use special cables (called crossover cables) or designated ports (called uplink ports) to daisy-chain switches together. Modern switches don’t require this extra consideration. Instead, you can daisy-chain two switches simply by connecting any port on the first switch to any port on the second switch.

https://www.dummies.com/programming/net ... -switches/

Hi All,

I have four network switches connected together, a four way one to the router, a seven way and another four way to the first four way and a 24 way one connected to the seven way one. All of them have PCs connected to other ports and all of them see the internet.

All are 'dumb' ie, no setting up required and all worked straight out of the box.

Pinching Chris's idea: These aren't modern switches by any means but any port and a standard network cable is all that's required to connect them together. all are D-Link if it matters?

Mark

Maybe one of the switches is a hub, as I read that switches work at Layer 3 (of the OSI model) and therefore have nothing to do with IP addresses.

That makes sense as mine get their IP addresses assigned by the router.

Do you have the model numbers Neil?

will check model numbers later. one is an old SMC switch wihich i investigated last night. it unmanaged, plug and play, auto speed, auto negotiate. the 24 port Tp-Link is another unmanaged switch which i bought recently as the 8 port was to small for my growing amount of connected devices

solved the problem. removed the switch and used 2 x usb wifi dongles. 300mbit is fast enough to transfer BOINC data.

chriscambridge wrote: ↑Wed Oct 31, 2018 7:58 pm Its funny you should mention this as i'm just about to buy a couple of switches for the server and other stuff. It was my understanding that you could just daisy chain them from the router, attaching pcs off each switch and all would work normally? As in Tim's diagram.

Am I right in thinking this will only work with unmanaged switches eg plug and play?
Is a 'dumb setting' the same as unmanaged?

Hi Chris

Most "switches" are indeed dumb or unmanaged...so, they can be daisy chained, as long as the router supports the number of ports you want to use.

So, you can use up to 255 ports on a specific port range...say 192.168.1.1 up to 192.168.1.255 (as 192.168.1.0 would be the ip addy for the originating port).

But some routers might only allow a specific number of ports to be accessible...that you can find that out in the router settings (usually under the LAN settings).

So, even if you had 255 ports available, via as many switches as you care to daisy chain, if the router only allows 10 ports (say 192.168.1.1 to 192.168.1.10) then even with a 24 port switch, then PC #11 wouldn't be allowed access (if the other 10 were powered up).


Another thing to be careful of, is that some switches have dedicated "uplink" ports - so this is the network socket that is used to connect to the router (or another switch higher up the chain, heading towrds the "internet" end of the chain).

Of course if it's a managed switch (or a hub), then it should have it's own admin screen, and that could easily have been set to a different IP address (either by previous user or the default), so connecting it to a router will not neccessarily allow any PC connected to the managed switch to "see" the internet.

You need to find the manual (and see what the default IP is), and check the managed switch admin screen to see if it is set to the same range as your router.

The router (gateway) could be set on 192.168.1.0 but if the switch is set to operate on the 192.168.2.x range (or any other IP range), then they won't talk between them.

You'd need to set the managed switch to use IP 192.168.1.1 and it would use the gateway 192.168.1.0

The switch could then be set to NOT be in DHCP mode, as the router would usually handle that. Or you can switch off DHCP and then assign manual IP addresses to each PC, as long as they are in the range of the router gateway IP (in this instance 192.168.1.x, where x is set to be unique to each PC).

regards
Tim

Noted; thanks for the heads up.