Catalyst3650 not connected routed port

[泡爺]

Hello expert of everyone.

On the Catalyst 3650, when I changed IOS to 16.3.11, the Routed Port that had speed set to 100 and Duplex set to Full no longer links up.

It was connected to the Switch with a cross cable. And before changing IOS, Link Up was done.

When I changed the speed setting from only 100 to auto and 100, I was able to link up.

As a test, I checked another Catalyst 3650 with the same IOS and a speed setting of only 100, and found that it was Link Up.

I don't know what's causing the problem.

Is it a mechanical failure or is there a problem with IOS?

Can you give me some advice on what to look for?

Thank you regard everyone.

～～～～～～Japanese～～～～～～～

こんにちは　エキスパートの皆さん。

Catalyst3650で、IOSを16.3.11に変更したところ、speedを100、DuplexをFullに設定していたRouted PortがLink Upしなくなりました。

クロスケーブルでSwitchとつなげていました。そしてIOSを変更する前は、Link Upができていました。

speedの設定を100だけからautoと100に変更したところ、Link Upできました。

試しに、もう1台のCatalyst3650で、同じIOSで、speedを100だけの設定で確認したところ、Link Upすることがわかりました。

なにが問題を起こしているか、私にはわからなくなりました。

機械の故障なのでしょうか、それともIOSに問題があるのでしょうか。

なにを調べればよいか、アドバイスをいただけないでしょうか

ありがとう、みなさん。

[Leo Laohoo]

What happens if you use a different port without a config?

[Georg Pauwen · Accepted solution]

Hello,

I found the bug below. Try a straight cable with hard coded speed and duplex, or change the settings to auto negotiate/auto MDIX.

3650 - Disabling Speed and Duplex or Auto MDIX Causes Link Down
CSCuv20618
Description
Symptom:
Link will not come up when manually setting speed and duplex or entering no mdix auto

Conditions:
Hard coded Speed and Duplex or no mdix auto is configured from cli.

In usual, when connect two Cisco switch device, using cross cable will link up normally, but if Hard coded Speed and Duplex or no mdix auto is configured on 3650, then can't link up by cross cable, but link up by straight cable.

Workaround:
Use Auto Negotiation for Speed / Duplex, and auto MDIX.

Further Problem Description:
this behavior is not seen when no mdix auto is removed and speed and duplex are allowed to auto negotiate.

[泡爺]

Thank you, Georg.

Does this still apply to this issue?

Known Fixed Releases:
16.3.11

It was written like this, so I wondered if it was different, but I'm sorry.

thank you everyone.