cable reversed in a switch

yankinlk

quick question...if i plug a normal, straight through network cable into a switch in port 1 and then plug the other end of the same cable into port number 2.....what happens? any issues/problems that might arise? Looking for major issues that might result from said cable "mistake".

1. the network is small, only 30 or so workstations, all running windows 98, tcpip.

2. they all get their address from the server using dhcp.

3. the switch is unmanaged. an allied telesyn, not sure the model number.

thanks for your help

Kali

Very strange question

Is port 1 the uplink port?

I can't see any need for it to be there at all, and why you'd want to is beyond me as well... if anything it would just add the MAC address of the switch back into its own routing table.. and it'll just be ignored as per usual.

Kali

I should add its probably not going to affect the rest of the network in the slightest, since thats what you seemed to be hinting at. (If it works as I've mentioned above... and it should)

yankinlk

well spotted kali, this is the "report" i was presented with by a troublesome customer, that brought in an expert to check the network...

"When a switch is initially powered up on a network it begins to "learn" the location of all active hosts on the network. Unfortunately this looped cable, connecting two ports within the same switch, provided a continuous and sustained source of confusion/misinformation to these devices, which ordinarily would constitute the intelligent backbone of the entire cabling system.

The result was found to be a network, which performed erratically. Some of the hosts (server and clients) were at times being brought to a complete standstill by the spurious datat which persisted in hogging the network bandwidth. the processing power of the hosts was continually being wasted in the examination of this data."

spongebob

arp arp arp

yankinlk

so is this answer text book crapola or is it legit? I still doubt there was ANY network problems...although the teachers (yes it was a school, dont do charity for schools it aint worth it) claim " its running MUCH faster now"

spongebob

ARP ARP arp arp ARP

Beëlzebooze

If the switch recieves a broadcast, it could concievably create a broadcast .
That is why the cable should not be there.

Beëlzebooze

it could create a broadcast STORM was what i was trying to say.

That is why when you have redundant links between switches STP (if your switch supports STP) makes sure one of the ports is "disabled" as it, again, could be the cause of broadcast storms.

acous

i think that's what he means by ARP ARP ARP