Member Avatar for aoparasite

Hello all,

I am new here and trying to find some answers to some basic networking questions. As the described in the title that is the problem that I am having. I am attempting the connection as follows: cable modem to Linksys wireless N router to a SmartLink ESK-108 8 port ethernet auto sensing switch with an end result of no connectivity. My router is set up to provide IP addys through the DHCP. However, when I connect the switch, I get a totally different IP range. Basic set up from the router is 192.168.bla.bla. When I check the network details with the switch connected I get a 169.254.239.69. I have tried a different switch, same brand, with the same end result.

This is what I have trouble shooted thus far.
Connected my server, which is maintained through a static IP, and configured the laptop for a static IP to the switch. I was able to get to the files on my server, however I was still unable to connect to the internet. I also noticed that my wireless connection would not function after the static config. I reset the laptop to obtain auto, but then I couldn't get to my server. I got the 169 IP.

It would appear that the switch is not allowing my DHCP to provide IP's. There is not a 'reset' button and I have looked for this particular model but came up with squat. Is there something that I need to configure in my router to detect the switch? At this point I am stumped. I was under the impression that an auto sensing switch was a basic add on with no problems.

If any more info is needed I would be glad to provide. FYI, I am a bit more experienced than the novice user, but there is still a lot I do not know. Any help would be greatly apprecieted!

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  • Latest Post Latest Post by octavia lowe

Dani AI

Generated

169.254.x.x addresses mean the client failed to get a DHCP lease (APIPA — the OS self-assigns when no DHCP reply arrives). An unmanaged Ethernet switch is a transparent L2 device, so a functioning switch normally does not block DHCP. This narrows the likely causes to wiring/port choice, a bad cable or switch, the router’s DHCP not answering, a managed switch with VLAN/port-isolation enabled, or the cable modem needing a reboot after a topology change.

Try these isolation steps in order:

  1. Check ports and LEDs. Confirm the switch is plugged into a LAN port on the Linksys (not the router WAN/Internet port) and that the link/activity LEDs light on both the router and the switch for that port. Swap the cable and router LAN port if a light is missing.
  2. Bypass the switch. Plug a laptop directly into a router LAN port with DHCP enabled and run ipconfig /renew (Windows) or the equivalent on other OS. A successful lease proves the router DHCP is working.
  3. Reintroduce the switch. If DHCP stops only when the switch is between devices and router, try a different switch port, another known-good cable, or a different switch make/model. If the switch is “smart/managed,” factory-reset it and check for VLANs or port isolation.
  4. Inspect DHCP and gateway. On a machine that gets a lease, use ipconfig /all to confirm the DHCP server IP and default gateway are the router. If static addressing allowed local server access (as @aoparasite reported) but not Internet, that indicates either an incorrect gateway/DNS on the static hosts or the router not NATing the LAN traffic.
  5. Power-cycle the cable modem after any change upstream (modem can bind to a MAC and refuse new devices until rebooted).

Typical fixes: correct the LAN-port wiring, replace the cable, power-cycle the modem/router, or reset a managed switch to defaults to remove VLANs. If these tests still show 169.254 leases, try one more test with a simple, known-good unmanaged switch to rule out device-specific quirks.

Member Avatar for aoparasite

Other than the switch being bad, does any one have any answers?

Member Avatar for octavia lowe

Hi i was wondeing if someone can help me. ive just come to japan for the year to teach and am desperate. I signed up for BB Yahoo Japan so i could have internet at home. HOwever my sony viao laptop is not registering the modemn they sent me and tells me i am not connected to the internet even though on the BB yahoo helpline they say i am. I have tried various things to do with the Local area connection but i just cant get it to work. do i need to put in an ip address or something? BB Yahoo tell me that they cant help me, no one here speaks english and my comptuer is in english so i cant take it to a store. I have no idea what to do. I have had the comptuer for 4 years and it has worked perfectly with internet around various student flats in Edinburgh and at my home in southern england. There is sometimes things which have to be changed in the intnernet settings when i first link up to a new intnernet but i cant remember what it was / is.
I am terrified i will be living in southern japan for a year with no internet or skype. please does anyone know what could be wrong? or a number i could ring to get it fixed?
Thanks

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