Reset port to default settings

[plsikk]

Hello.

I have a question. Is exist any equivalent for FortiGate and fortiswitch like for cisco - 

default interface-type interface-number

 I have a problem with one setup and I don't have any idea why links between switches are down

Those two red link are missed from fortilink. on lest switch ports 25 and 26 are connected , on right 17 on both.

Led not blinking. SFP modules replaced, fibers also. But what is really weird if I put ports 25 and 26 on left top, right switches are still online

 I don't have any idea why those two links are not working. Tried also setup speed on left to auto, 1000auto,1000full, nothing help.

Tried also connect another forthiswitch to port 25 but still the same. on this switch led are not blinking but on second switch link is up and led are on.

Transceivers are recognized correctly 

Any ideas how to troubleshoot . Black scenario is  reset left to factory and reconfigure again .

Models

Left 224D

Right_ 424E-Fiber

FortiOS 7.2.4

Fortigate OS 6.4.14

[AEK]

Hello

You can reset a port settings one by one, using the following the "unset command". Example below:

config system interface
  edit port 1
    unset speed
    unset type
    unset mode
  next
end

Regarding your issue, I didn't try connect MLAG to MLAG before, but I think it is normal behavior to prevent loop.

Try remove connections from top left switch to right switches, just to see if the connections with bottom left come up.

[BSeklecki_GE]

@plsikk : Have you checked the DOM report of the SFP?  Need to know if this is an OSI Layer1 problem or an OSI Layer2 problem (Like an LACP problem causing the switchport to voluntarily shut down as suggested by @AEK )

IOS# show interface [x] transceiver

FG# get sys interface transceiver FG# get switch modules detail FG# get switch modules status FG# diagnose switch physical-ports summary

@AEK  In the Cisco world, an LACP or MC-LAG problem would result in the LED being Amber, not blank/off; I hope it is the same in the realm of FortiOS.

[plsikk]

Thank You for you answer, Will try inset all options . 

Regrading MCLAG-MCLAG connection it is typical Multi-tier MCLAG architecture, I have few locations configured lite this, so I think it is not the issue in this case, 

[BSeklecki_GE]

Also, if the DOM table show the RX and TX light levels are good and the absence of ALARMS, and you suspect that your problem it is caused by an LACP issue:

show lacp status show lacp show etherchannel summary show etherchannel 1 detail

FG# diagnose netlink aggregate name [name]

Or LACP seems agreeable, then the next layer up is (within OSI Layer2) is STP; if you suspect Spanning Tree: 

show spanning tree

FG# get sys stp list FG# diagnose sys stp status

[plsikk]

I'm waiting to local resources on remote site which connect links again. I'll let you know about status later

[plsikk]

OK, We worked on this topic few hours , and we didn't found solution. Only one helped. Issue fixed by factory reset left bottom switch. Then link come up. Maybe some misconfiguration in switch or FG. Also this switch has been removed from FortiGate and re-joined. Now is fine