GS724T Port configuration

[Nakimushi]

Hi everyone,

The company I worked for have some old switches, something like below.

Model Name GS724Tv3 

Boot Version B5.1.1.1

Software Version 5.4.2.9
 

I've been trying to use the "Port Configuration" to limit the speed from 1G to 100Mbps by changing the port speed.

Yet, the results are not what I expected.

Without the limitation, I can get 800Mbps with speedtest.net, as soon as I change the limitation to "100Mbps Full Duplex", the speed dropped to around 30Mbps

Any suggestion what I've done wrong?

[schumaku · Accepted solution]

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@Nakimushi wrote:

Model Name GS724Tv3 

Software Version 5.4.2.9
 ...

Without the limitation, I can get 800Mbps with speedtest.net, as soon as I change the limitation to "100Mbps Full Duplex", the speed dropped to around 30Mbps

---

Just attempt to force an Ethernet link rate to 100 Mb/s alone does not limit the throughput to the theoretical possible link rate. Whatever happens on the link, whatever the computer connected does make out of it - it's obviously not what you expect. Collisions, CRC errors, probably even CRC errors are predictable, the speed drop does proof.

If you are in seek of something more intelligent, CoS Interface Configuration can become your friend, start with the RT*M, then Interface Egress Shaping Rate resp. Interface Ingress Rate Limit could become your friends (or not). Steep learning curve ahead.

[schumaku · Accepted solution]

---

@Nakimushi wrote:

Model Name GS724Tv3 

Software Version 5.4.2.9
 ...

Without the limitation, I can get 800Mbps with speedtest.net, as soon as I change the limitation to "100Mbps Full Duplex", the speed dropped to around 30Mbps

---

Just attempt to force an Ethernet link rate to 100 Mb/s alone does not limit the throughput to the theoretical possible link rate. Whatever happens on the link, whatever the computer connected does make out of it - it's obviously not what you expect. Collisions, CRC errors, probably even CRC errors are predictable, the speed drop does proof.

If you are in seek of something more intelligent, CoS Interface Configuration can become your friend, start with the RT*M, then Interface Egress Shaping Rate resp. Interface Ingress Rate Limit could become your friends (or not). Steep learning curve ahead.