At the beginning I will sorry for me English I^m originally polish. I will try me best to ask understandable question.
I have very complicated problem but I'm sure the answer is easy.
I bought switch netgear GS748T it was working fine few month and then starts problems. Once per day it stop working yo I need to restart and like that every day. I put different netgear switch FS726T in his place and everything was working fine.
I send switch back and receive new one and he has similar problems so i send them back this switch and wait for another replacing switch. Network was working on FS726T without any problem.
I bought another switch this time linksys SLM2048 I connect him and then on this switch some of the pc was working fine some doesn't work at all. I use the same cable us for FS726T i try to connect to different ports reset switch nothing help. Then I change cable and works fine on other cable.
So I thought is cable but I install second card on one of the pc and connect with the cable that first card was not working and second card works fine.
I tested 15 different cables and sometimes i didn't have connection at all icon with red cross on PC
sometimes i have limited connection that means i can send but I don't receive. But the same cables connected to other switches in company works fine. I have simply LAN tester all cables looks fine some of them i did(I thought that must be reason) but some of them was bought in shop and still the same.
I live network like that and I receive again netgear GS748T because of some mistake i receive two unit(I'm not complaining) I connect them to the linksys and I connect one PC on each for testing
and here is problem like that that is working fine one day and then on one of them i loose ping to him but i can ping pc that is connect to him but ping are very slow like 40 ms or more but pc is working fine.
On second netgear I connect works fine I can ping him PC on this switch also works fine so i decide to put PC from the first netgear with slow connection to the second switch but when i plug cable nothing happens limited connection after reset both of them everything back to normal.
On the first netgear when I unplug cable the light is still flashing on switch like the connection is still activeted.
ANY idea what is problem. I don't thing is switches because I use five different looks like cable but how can I test them.
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