Network issue

We have an issue at the office that I'm trying to get resolved.

Right now at our office we just placed a new office and it is attached to our network. The network had room in the switch, the patch panel looks to be done right. Ran a test for diagnostics and it passed. However, when i connect a computer to it from the new office, the NIC on the PC is unable to connect. It flashes 5 times and then it shuts off since it was unable to connect. Next, I placed a 5 port switch next to the computer and then plugged it into the NIC and it was working fine. Can anyone help with an explanation for this?

Find more posts tagged with

Save $250 on 2025 certification boot camps from Infosec!

Book now with code EOY2025

Button

Comments

santaowns

Check the cables. Verify ports plugged in and on switch it is not admin down.

networker050184

What is the switch showing you (assuming you can login and take a look)? Could be numerous things.

JasonIT

Is the port on the switch in an In Service and UP state?

rsutton

Some things that come to mind to check for:
-Duplex settings on the switch need to be compatible with the computer
-Switch port needs to be active/up
-Are you doing any authentication on the switch?

mistabrumley89

^Agreed. I would check the duplex settings. I've even had to hard code the speed sometimes on the switch from some funky NICS. Does the switch give you a duplex mismatch log? Port flapping? Cable issue?

it_consultant

dj_kenshin wrote: »

We have an issue at the office that I'm trying to get resolved.

Right now at our office we just placed a new office and it is attached to our network. The network had room in the switch, the patch panel looks to be done right. Ran a test for diagnostics and it passed. However, when i connect a computer to it from the new office, the NIC on the PC is unable to connect. It flashes 5 times and then it shuts off since it was unable to connect. Next, I placed a 5 port switch next to the computer and then plugged it into the NIC and it was working fine. Can anyone help with an explanation for this?

Based on the fact that if you plug in a switch and then plug in the computer to the switch and it works then it is not cabling. Duplex is a possibility, if the port is hard set to a gig and your 5 port switch has a gig-uplink and 10/100 ports and your NIC is 10/100, this could explain that phenomenon. The other possibility is that the switch is set to rSTP link type point to point which would mean that the only thing it will allow on the other end of that link is another switch - though this is a bit of a stretch. I would also check to see if there is any layer-2 authentication switched on that port, that can have some funky symptoms.