[SOLVED] Netgear GS748Tv5

[doesitmatter9]

Hi,

Please bear with me as I'm not an expert on networking by any means, however I have a problem with my network and my best guess is that it is do with the switch (GS748Tv5).

My network is as follows

Internet provided via Sky (UK) via their supplied router. Router plugged into RJ45 leading back to GS748Tv5 which then supplies RJ45 connections to each room in the house etc. As of today I have no Internet, I'm not sure if it is related but yesterday I changed my SSID on my router to match some access points supplied by UniFi (this is what triggered the problem, although I'm not sure why). I reset my sky router back to factory defaults and the wifi works fine and if I plug my PC direct to the router I get internet.

If I connect my PC to the switch and the switch to the router I get no valid IP configuration in windows. I've tried various guides on youtube but nothing helps. I'm able to detect the switch via SmartControlCenter but opening the web page access does not work, it says that page can't be reached. I've factory reset my switch and still get the same problems. When I click on maintenance within SmartControlCenter it says that the device (my PC I assume) is on a different subnet to the switch. within IPconfig my subnet mask on the ethernet adaptor is 255.255.0.0 but on the switch it is 255.255.255.0 (no idea if this is how it should be or not).

If I connect my PC to the router and have a separate RJ45 from the spare port on my router to the switch the switch is not discovered in SmartControlCenter.

Any help would be much appreciated.

 

[kanewolf]

Hi,

Please bear with me as I'm not an expert on networking by any means, however I have a problem with my network and my best guess is that it is do with the switch (GS748Tv5).

My network is as follows

Internet provided via Sky (UK) via their supplied router. Router plugged into RJ45 leading back to GS748Tv5 which then supplies RJ45 connections to each room in the house etc. As of today I have no Internet, I'm not sure if it is related but yesterday I changed my SSID on my router to match some access points supplied by UniFi (this is what triggered the problem, although I'm not sure why). I reset my sky router back to factory defaults and the wifi works fine and if I plug my PC direct to the router I get internet.

If I connect my PC to the switch and the switch to the router I get no valid IP configuration in windows. I've tried various guides on youtube but nothing helps. I'm able to detect the switch via SmartControlCenter but opening the web page access does not work, it says that page can't be reached. I've factory reset my switch and still get the same problems. When I click on maintenance within SmartControlCenter it says that the device (my PC I assume) is on a different subnet to the switch. within IPconfig my subnet mask on the ethernet adaptor is 255.255.0.0 but on the switch it is 255.255.255.0 (no idea if this is how it should be or not).

If I connect my PC to the router and have a separate RJ45 from the spare port on my router to the switch the switch is not discovered in SmartControlCenter.

Any help would be much appreciated.

My guess, and it is just a guess, is that you have a loop in you network. Did you also update firmware on your UniFI harware? A new FW version just went "stable" so it may have showed up in your controller. Do you have "Uplink Connectivity Monitor" enabled in your controller? If so you might have a wireless mesh happening that is confusing the switch with a loop.

 

[bill001g]

Hard to say what started all this but I suspect your current issues with the switch is you factory reset it.

You now need to change the management IP to be in the same subnet and mask as your main network. Hard to say without reading the manual what the default configuration is. You want all the ports as well as the management port all assigned to 1 vlan. If you have different requirements you need to make the appropriate changes.

I would unplug everything from the switch except your pc as you start. Then plug in just the router and get that working. If you add other devices and it causes problems you will at least know which device is causing it.

 

[doesitmatter9]

My guess, and it is just a guess, is that you have a loop in you network. Did you also update firmware on your UniFI harware? A new FW version just went "stable" so it may have showed up in your controller. Do you have "Uplink Connectivity Monitor" enabled in your controller? If so you might have a wireless mesh happening that is confusing the switch with a loop.

My guess, and it is just a guess, is that you have a loop in you network. Did you also update firmware on your UniFI harware? A new FW version just went "stable" so it may have showed up in your controller. Do you have "Uplink Connectivity Monitor" enabled in your controller? If so you might have a wireless mesh happening that is confusing the switch with a loop.

I haven't performed any firmware update. I've not removed the controller from Unifi completely and disconnected it.

 

[doesitmatter9]

Hard to say what started all this but I suspect your current issues with the switch is you factory reset it.

You now need to change the management IP to be in the same subnet and mask as your main network. Hard to say without reading the manual what the default configuration is. You want all the ports as well as the management port all assigned to 1 vlan. If you have different requirements you need to make the appropriate changes.

I would unplug everything from the switch except your pc as you start. Then plug in just the router and get that working. If you add other devices and it causes problems you will at least know which device is causing it.

I've got myself into quite the mess here it seems!

Sorry to be a complete idiot but I'm a bit lost. Are you saying I need to change the IP address of the switch and subnet to that of my PC, if the switch is connect to my PC only? If so how do I know what IP address to assign it? I've never had to do anything like this before and don't really know what I'm doing. I'm contemplating just ordering a new bloody switch but it seems like a waste.

 

[kanewolf]

I've got myself into quite the mess here it seems!

Sorry to be a complete idiot but I'm a bit lost. Are you saying I need to change the IP address of the switch and subnet to that of my PC, if the switch is connect to my PC only? If so how do I know what IP address to assign it? I've never had to do anything like this before and don't really know what I'm doing. I'm contemplating just ordering a new bloody switch but it seems like a waste.

Generally a single class C network is all that is needed for home ( 255.255.255.0 netmask).
You have some managed devices (APs and switch). Do you have VLANs?

 

[doesitmatter9]

Generally a single class C network is all that is needed for home ( 255.255.255.0 netmask).
You have some managed devices (APs and switch). Do you have VLANs?

Not to my knowledge.

The Netgear switch has a program called SmartControlCenter. This lets me change the switch IP, Subnet and Gateway assuming I disable DHCP. Upon doing this it says that IP and Gateway must confine to Subnet. I don't really know what IP, Gateway or Subnet to tell it to assign.

 

[doesitmatter9]

I have a Netgear DS918+ Nas if that impacts anything.

 

[kanewolf]

I have a Netgear DS918+ Nas if that impacts anything.

I think you mean Synology DS918+ ...
You have some advanced network gear, and it sounds like you are beyond your knowledge.
If it were me, I would start by building a list (probably in Excel) of all your network devices. List which are DHCP and which are (or should be static). Things like the APs, printers, switches and your NAS are usually static IP.
Look on your router and identify the DHCP section. It will show an IP address base like 192.168.10.0 for example. It will say that that DHCP range is 2 - 100 for example. Assuming that you are OK with the subnet (192.168.10.x) then you would decide the static IPs for all your fixed equipment.
The network gear might get .240 - 254 for example. So the switch, APs, a cloud key and your NAS would all get IPs of 192.168.10.240 to 192.168.10.254.
That is what you would configure in these devices.
BUT, I think you really need somebody with some experience with networking to help you with hands-on or at least over-the-shoulder guidance. Nothing you need to do is difficult, but there are lots of places to make mistakes.

 

[doesitmatter9]

I think you mean Synology DS918+ ...
You have some advanced network gear, and it sounds like you are beyond your knowledge.
If it were me, I would start by building a list (probably in Excel) of all your network devices. List which are DHCP and which are (or should be static). Things like the APs, printers, switches and your NAS are usually static IP.
Look on your router and identify the DHCP section. It will show an IP address base like 192.168.10.0 for example. It will say that that DHCP range is 2 - 100 for example. Assuming that you are OK with the subnet (192.168.10.x) then you would decide the static IPs for all your fixed equipment.
The network gear might get .240 - 254 for example. So the switch, APs, a cloud key and your NAS would all get IPs of 192.168.10.240 to 192.168.10.254.
That is what you would configure in these devices.
BUT, I think you really need somebody with some experience with networking to help you with hands-on or at least over-the-shoulder guidance. Nothing you need to do is difficult, but there are lots of places to make mistakes.

Sorry you're quite right, it's a Synology.

It's fair to say I've always been very reliant on the plug and play aspect of most things.

The router says the starting range of IP is 192.168.0.2 and ends with 192.168.0.254.

The issue I have is that I can't access the switch via the router. If I connect to the switch from my PC the Netgear app detects the switch but it won't let me change the IP address.

I think I need someone to fix it but in the current climate that's a non starter. Might just buy a new switch and try and sell this one to someone who knows how to fix it.

Thanks for your help, most appreciated!

 

[kanewolf]

Sorry you're quite right, it's a Synology.

It's fair to say I've always been very reliant on the plug and play aspect of most things.

The router says the starting range of IP is 192.168.0.2 and ends with 192.168.0.254.

The issue I have is that I can't access the switch via the router. If I connect to the switch from my PC the Netgear app detects the switch but it won't let me change the IP address.

I think I need someone to fix it but in the current climate that's a non starter. Might just buy a new switch and try and sell this one to someone who knows how to fix it.

Thanks for your help, most appreciated!

OK Your router is using the ENTIRE address range for DHCP. You need to lower that top number to something like 100 or at least 200. That way you have space for your static IPs so they won't conflict with DHCP. The address conflict may be your primary problem.
A factory reset on your switch may be the next step. You may not be able to change the IP address because it is set via DHCP. Check that setting.

 

[doesitmatter9]

OK Your router is using the ENTIRE address range for DHCP. You need to lower that top number to something like 100 or at least 200. That way you have space for your static IPs so they won't conflict with DHCP. The address conflict may be your primary problem.
A factory reset on your switch may be the next step. You may not be able to change the IP address because it is set via DHCP. Check that setting.

I changed it to 150.

At the moment I've got my PC connected to the router and my router to the switch via the spare ethernet port. If I do factory reset the switch resets but it isn't detected in the SmartControlCenter. The only way I can detect the switch is if I plug an ethernet direct from my PC to the switch, however I then can't change the IP address or subnet on the switch.

 

[kanewolf]

A factory reset should cause your switch to act like a dumb switch. The IP isn't required for it to function.
Disconnect the switch from the router, reboot the switch and connect your PC to the switch. Then set a static IP on your PC, something like 192.168.0.200 --
And then use a web browser to access your switch -- http://www.downloads.netgear.com/files/GDC/GS716TV3/GS716Tv3_GS724Tv4_GS748Tv5_IG_EN.pdf
I am not a fan of the applications. Always use a browser when possible.

 

[doesitmatter9]

A factory reset should cause your switch to act like a dumb switch. The IP isn't required for it to function.
Disconnect the switch from the router, reboot the switch and connect your PC to the switch. Then set a static IP on your PC, something like 192.168.0.200 --
And then use a web browser to access your switch -- http://www.downloads.netgear.com/files/GDC/GS716TV3/GS716Tv3_GS724Tv4_GS748Tv5_IG_EN.pdf
I am not a fan of the applications. Always use a browser when possible.

Thanks I think we've made some progress!

So I changed the IP address on my PC to 192.168.0.200 in ethernet properties > TCP/IPv4 > properties. I was then able to use the browser to access the switch. I tried connecting the router to the switch but didn't get an Internet connection?

 

[kanewolf]

Thanks I think we've made some progress!

So I changed the IP address on my PC to 192.168.0.200 in ethernet properties > TCP/IPv4 > properties. I was then able to use the browser to access the switch. I tried connecting the router to the switch but didn't get an Internet connection?

Once the switch is connected to the router, then you want to change your PC back to DHCP rather than static.

 

[doesitmatter9]

I connected to the switch via static ip set on my pc. Once logged in via internet browser I changed back to dhcp on pc. Once I did this I ran ipconfig and found I had an IP address of 169.254.242.153 subnet 255.255.0.0

 

[kanewolf]

I connected to the switch via static ip set on my pc. Once logged in via internet browser I changed back to dhcp on pc. Once I did this I ran ipconfig and found I had an IP address of 169.254.242.153 subnet 255.255.0.0

What do the LEDs on the switch show? Do you have normal connectivity LED lights on the link to the router?

 

[doesitmatter9]

I have green between pc and switch and amber between switch and router. I believe this is to do with the transfer rate?

 

[kanewolf]

I have green between pc and switch and amber between switch and router. I believe this is to do with the transfer rate?

I would swap the cable between the switch and router. Any new router is a gigabit router. That cable might be suspect.

 

[doesitmatter9]

I would swap the cable between the switch and router. Any new router is a gigabit router. That cable might be suspect.

For what it's worth when i connect my pc to the router directly and gain internet my IP is 192.168.0.6 subnet 255.255.255.0.

Its like there is a problem with the router communicating with the switch and vise versa.

 

[kanewolf]

For what it's worth when i connect my pc to the router directly and gain internet my IP is 192.168.0.6 subnet 255.255.255.0.

Its like there is a problem with the router communicating with the switch and vise versa.

Yeah, that is why I would start with the cable.

 

[doesitmatter9]

Yeah, that is why I would start with the cable.

It looks like you were right with the cable. Changed it to a new one and got a green connection, one minute later internet access gained! The router assigned the switch a new IP address and we're in business.

Thank you so much for your help!! You just saved me £250 on a new switch