Intermitent Link

[XFreitas]

Hi.

Recently I've been receiving multiples log messages as shown below:

Jul 16 11:57:46:540 2019 MSTP Information MSTP_FORWARDING Instance 0's port GigabitEthernet1/0/5 has been set to forwarding state.
Jul 16 11:57:46:526 2019 IFNET Error LINK_UPDOWN GigabitEthernet1/0/5 link status is UP.
Jul 16 11:57:40:392 2019 IFNET Error LINK_UPDOWN GigabitEthernet1/0/5 link status is DOWN.
Jul 16 11:57:38:647 2019 MSTP Information MSTP_FORWARDING Instance 0's port GigabitEthernet1/0/5 has been set to forwarding state.
Jul 16 11:57:38:632 2019 IFNET Error LINK_UPDOWN GigabitEthernet1/0/5 link status is UP.
Jul 16 11:57:22:995 2019 IFNET Error LINK_UPDOWN GigabitEthernet1/0/5 link status is DOWN.
Jul 16 11:57:22:936 2019 MSTP Information MSTP_FORWARDING Instance 0's port GigabitEthernet1/0/5 has been set to forwarding state.
Jul 16 11:57:22:922 2019 IFNET Error LINK_UPDOWN GigabitEthernet1/0/5 link status is UP.
Jul 16 11:57:13:056 2019 IFNET Error LINK_UPDOWN GigabitEthernet1/0/5 link status is DOWN.
Jul 16 11:57:13:045 2019 MSTP Information MSTP_FORWARDING Instance 0's port GigabitEthernet1/0/5 has been set to forwarding state.
Jul 16 11:57:13:031 2019 IFNET Error LINK_UPDOWN GigabitEthernet1/0/5 link status is UP.
Jul 16 11:56:59:116 2019 IFNET Error LINK_UPDOWN GigabitEthernet1/0/5 link status is DOWN.
Jul 16 11:56:58:752 2019 MSTP Information MSTP_FORWARDING Instance 0's port GigabitEthernet1/0/5 has been set to forwarding state.
Jul 16 11:56:58:738 2019 IFNET Error LINK_UPDOWN GigabitEthernet1/0/5 link status is UP.

The topology is base in one switch core(HP 1920G) and two child switchs(HP 1920S & Dell Networking) connected to the core, so when the core or the media converter are turn off and turn on, the connection gets intermitent.

Please I need help.

[VoIP-Buddy]

Xfreitas,

That's called port flapping.  What device is on 1/0/5?  If it is something like a PC, printer, VoIP phone, or some other end system, you can set the port as an edge port and Spanning Tree will not be affected.  The way it is now, every time that happens, the tables that track the device, ARP and MAC, are cleared and the entries have to be re-learned.  That takes a little time and causes service disruption and potentially a performance hit.

Rgards,

David

[XFreitas]

Hi David

First of all, I really appreciate your answer.

Well, I found what was connected in that port, but my problem keeps and I don't know why.

For example, I've received a lot of these logs messages today, but the interface wasn't the same, it was another switch connected to the swicht that fired these logs.

So, the only thing that I did to fix this was trying to connect the cable in another interfaces until the connection was established and stabled.

This problems started anoying me after I installed two Media Converter (TP-LINK-CONVERSOR DE MIDIA TPLINK 1000 MBPS RJ45 -MM 550 M SC) between the switchs.

Could it be a STP problem between the media converters and the Switches(HP 1920S and HP 1920G)?