Wired Network Problem

[Will172]

Hello!

Firstly I am not that techy – so please forgive my ignorance I am learning all this on the fly.

I have started to set up a wired network at work (a very small business). Currently we have a wireless network that everyone's Mac's connect to. It's all very standard, a default BT Homehub 5 setup (I am in the UK), 5 mac's, 2 printers, couple of backup HDDs etc.

Transferring big files between mac's was taking time, so we wanted to upgrade to a wired network and try and get a gigabit LAN going.

The building we are in has ethernet ports next to where each Mac is (x5). They then are essentially just extension cables that pop out all in the same place where I can then plug them in to the switch.

I have a 16port switch and Cat6 UTP Patch cables for everything getting wired in (D-Link DGS-1210-16).

So the setup is roughly like this:
-------ADSL/Phone-----Router-----Switch----Ethernet ports-----x5 Macs etc

So I initially did tests on the LAN to make sure that everything worked – and I successfully connected one mac through the ethernet port, through the switch, through the router to connect to the internet (it got assigned an IP and I could get on to bbc.co.uk etc with WiFi off.)

Then I connected all of the mac's to their respective ethernet port – at the other end I then put cables from the ethernet ports in to the slots on the switch, there is then one cable going from the switch to the router, then the ASDL cable goes in to a filter and in to the phone socket.

Now this is where I am getting stuck. The WiFi still works – so I know I am getting internet in to the office, but only some of the wired connections are working.

I get some lights flashing on the switch like the one that goes in to the router, and one of the ethernet ports in the office that has a printer connected to it. But nothing else works.

This would of led me to believe that there was just a problem with the ethernet ports, but I have tested a couple of them independently at one end and they have worked previously, but not anymore.

Am I missing something, or does anyone have any advice here? Hopefully I have explained this well enough for an answer!

Thanks in advance

 

[joex444]

Simplify your life for a minute and bring your laptop into the room with the switch. Just get a short Ethernet cable and plug one end into your Mac and then systematically plug the other end into different switch ports. You'll see that your 16 port switch (manual is available online, I'll link you at the end) is physically composed of four 4-port groupings. It's a smart switch, not an unmanaged switch so there may be some settings that it has which are causing your problems.

Now first of all you need to note the IP address that you get over WiFi. For example, if you received this:

IP 10.0.0.101
Subnet 255.255.255.0

then you *want* to see yourself get an IP address from the Ethernet port that matches 10.0.0.X and subnet 255.255.255.0. If your subnet was 255.255.0.0 then you'd want to see 10.0.X.Y, as the subnet can be loosely thought of as being composed of 255s and 0s - any position that is a 255 means that the number is locked down in the IP addresses it can communicate with, while any position that's 0 means it can be any value. (This is way too simple: you can actually have 255.255.255.128, for example, which means that the last position is split so 10.0.0.10 and 10.0.0.200 are on separate networks.) To make it clear why you need to verify this - only IP addresses that are in the same range (defined by the IP and subnet) are considered to be on the same network. These addresses should all be Private IP addresses (like the 10.X.Y.Z one above, but it could be 172.16.X.Y-172.31.X.Y (this is a subnet 255.240.0.0) or 192.168.X.Y). (Further note that if you did have a 172.16.X.Y address then you don't need subnet 255.240.0.0 -- you could have 255.255.0.0 or 255.255.255.0 and it would be OK.)

If for some ports you are getting IP addresses that are out of the range that the WiFi gives you then these ports are not setup correctly, and you are not hitting the router/Internet. Like I said, this switch is not an unmanaged one so it *may* have some configuration already existing on it that has certain ports setup as static addresses for an old network or something. Physically going in and checking them will be helpful - for example, you may find that 5 (or more) of the ports work for your network as-is and you can get those ports up and running then work on getting the rest to work while everyone else happily makes use of the wired connections.

Also note that there are some addresses which are basically error codes. These are 169.254.X.Y addresses.

Manual for switch: http://www.dlink.com/-/media/Business_Products/DGS/DGS%201210%2048/Manual/DGS_1210_Series_Manual_v4_00_EN.pdf

 

[Will172]

Okay – well this does make some sense to me. The only problem I have though is that from what I can tell in the instructions you linked (thanks very much for these) I need a PC to directly interact with the switch. Is that correct? Bit of a nightmare as I don't have one in the office if that is the case.

I got given the switch and told it would do the job, hence the lack of knowledge here.

Thanks for helping me out though!

 

[jsmithepa]

I need a PC to directly interact with the switch. Is that correct? Bit of a nightmare as I don't have one in the office if that is the case.

Am guessing the request to do this is to ascertain nothing wrong with the wiring. If these are existing office wall wirings, I doubt anything wrong with them.

I got given the switch

I perused the manual briefly and this is a pretty impressive piece of equipment, it's between a fully-managed and a dumb switch. Good news is it got a lot of features, bad news is, you have to understand how it works! My suggestion is, give it a RESET TO FACTORY and start from scratch, to make it function as a dumb switch, just to get things going. Then when you have more time to play with it, can pour over the manual at a later time.

 

[Will172]

Yeah I think a reset would probably be the best option. I will work my way through the manual and figure out the IP and Subnet business!

Hopefully that works! Thanks!

 

[Will172]

I have just hit a problem.

So I understand that in order to connect to the switch to manage it the PC's ip address needs to be on the same numbers so if my switch's ip is 10.90.x.x my PC's ip needs to be 10.x.x.x. Have I understood that correctly?

The problem is that my router has internal ip address's of the standard 192.168.x.x. I do have the option of changing to a new number system (10.x.x.x) but it is telling me that I need to disable some public BT wifi thing to do it.

Is this all because I have plugged the router in to the switch? If I plug a PC directly in to the switch will that work? Can I manually give myself an IP in the right range?

Update..............

Okay so I was going wrong by trying to give myself the same IP as the switch I think. I have been able to get the login window up – but it's asking for a password.

I haven't set any passwords yet, and I have pressed the reset button a few times. I have scoured the instructions manual and I can't see anything about a default password.

Any ideas?

 

[Will172]

Okay me again.

The default password (depressingly) was admin...

So I managed to get on to the switch (yay) using the default ip 10.90.x.x by giving myself an ip in that range.

However am I right in thinking now that my problem is this conflict with the BT Wifi ip range and the switch?

Can you change the ip address of a switch manually? Or can I just set this switch as a dumb switch as someone mentioned before?

 

[jsmithepa]

In a typical scenario such as yours:

The subnet used is 192.168.0.x (where x=anything)
Mask is 255.255.255.0 (defines a class c network with max of 254 clients)

Now, a piece of equipment like your switch needs a static IP, so you should configure your DHCP to allow a range of static IP and not use them for dynamic clients, say 192.168.0.1 to 192.168.0.15. Your dynamically assigned IPs then starts at 16, this gives you 15 statics and 239 dynamics.

Once you have the DHCP re-configured, reboot everything, once again go into your switch and give it a static in that 1-15 range, and put a label on it.

More: Your router+WIFI boxes too should have static IP in the same range as I just defined, and sometimes by default they are assigned like 192.168.0.254, if you want to leave those alone, instead of having statics 1-15, you can certainly have the statics say 240-254, it won't make a difference, so you decide where this static range is gonna be, then stick to it.

 

[Will172]

Me again!

So I have managed to get everything on the same range of ip (10.x.x.x) the mask is and has always been 255.0.0.0 is that still going to work?

The Wifi still works and that's what we are still running on.

Some of the lights on the switch are flashing with activity as if they are doing something, but still the mac's don't even recognise that they have a cable plugged in.

Any ideas?

 

[bill001g]

I wish I was better at mac but are you saying the port is in a disconnected state or it just does not get a ip address. If you have lights on the switch that the mac is plugged into that generally means you have a good physical connection.

Although 10.x.x.x with a 255.0.0.0 mask is not something you commonly see it will work as long as everything supports it. Some routers are a pain and have stupid limitation. Be very sure you have the dhpc pools set correctly. But if your wireless clients are getting 10.x.x.x addresses everything is likely fine on the router.

Have you tried to set a static ip in the mac. If for example the router is now set to 10.0.0.1 and you set the mac to 10.0.0.50 you should be able to ping 10.0.0.1 from the mac. If you set say 10.0.0.50 on one mac and 10.0.0.51 on a second can you ping between the 2 devices.

 

[Will172]

Yeah so the wireless is now giving out ip addresses in the 10.x.x.x range.

One of the mac's is connected to the switch via the wall ethernet ports – and has an activity light – however it just says "Cable unplugged – Either the cable for Ethernet 1 is not plugged in or the device at the other end is not responding."

However my mac is plugged in to the wall ethernet and then in to the switch and I get no light and also "Cable unplugged –Either the cable for Ethernet 1 is not plugged in or the device at the other end is not responding."

However one printer is directly connected to an ethernet port to the switch – and that appears on the network and I can print from it. So I am really confused now.

 

[bill001g]

Managed switches are such a pain sometimes. It takes so long to really learn one manufacture.

I would get a long ethernet cable and run it down the hall....or carry a mac to the switch and use a short cable. If it still does not work then your wires in the wall are fine.

It sound like the port is in some disabled state in the switch. There should be a menu that show the port status. It should tell if the switch thinks the port is up or down and what duplex it negotiated. I wish I knew the manual is huge for that device.

 

[Will172]

Yeah I have seen that menu – it showed that some stuff was connected at 100m some at 1000m duplex or something. So it was seeing some stuff. But whenever I make a change to anything I then have to reset it to be able to access it again.

I am going to have another tinker in a bit.

 

[jsmithepa]

I am going to have another tinker in a bit.

Well that a good thing. You got this free toy, but it wants to spend time with you!

If you don't have time, a 16-port dumb switch is like usd$50. Plug&Play.

P25 of the manual, it shows ports can be DISABLED [gasp!]

Take a laptop to the switch and physically verify each port is OK to discount the wall wiring.

 

[Will172]

Well after pissing around with everything for what has felt like months (2days). I think that there is a problem with 2 of the ethernet ports themselves. I have tested each port direct – and get a flashing green light that shows up on software bit. However when I then connect my mac to a ethernet port then pop a cable at the other ethernet port and in to the switch I get no green lights.

So as far as I am concerned there is a problem with a few of the ethernet ports as the others do work.

Does that sound reasonable? Or is there something I have missed?