Internet link up and down in the same minute

Need to figure out - Is it the ISP or is it the UTM?  What network card is in the UTM?  There are incompatible cards that will do this, I have the issue myself in a SuperMicro on-board NIC, that will do this every second or so.

I would check your Kernel Message log and see if you have something like 'link is down', 'link is up' type pattern and post a copy of the logs here.

UTM is in VM, ISP links are separated in VLANs which means using same card. I already checked logs and didn't see any informations about link down or up.

Salut Daniel,

What virtual NIC are you using in the VM?

Amodin's suggestion seems to have paid off - it feels like the ISP's problem or an Ethernet cable to the ISP's equipment.

Cheers - Bob

Bonjour Bob and all,

e1000 is the libvirt driver used for WLANs. As I told, both ISPs connections are using the same link -Ethernet card being I350 Gigabit Network Connection- so server HW can not be involved. Another thing is that the customer have 5 locations, all equiped with the same HW, Sophos UTM version and 2 same ISPs- only this site have the problem with this one link.

Will replace cable from switch to ISP equipment.

Thanks.

Did changing the cable solve the problem, Daniel?

I don't remember the issue, but using e1000 virtual NICs seems to cause a problem with the UTM.  The recommended one is vmxnet3.  Does the problem persist if you make that change?

Cheers - Bob

Hello Bob. We changed the cable from switch to ISP router, and we have much less problems. In the mean time I asked ISP to fix the floow to 1000/full instead of auto (already done on our side), don't know if they did it.

Concerning the virtual NIC, I would agree if *both* ISP links would have the problem as all the traffic is going out with the same NIC using VLANs. Can give a try to vmxnet3 if problem still persistent.

On another site from this customer I faced problem with one VM (Asterisk on Ubuntu 20.04) where the NIC was e1000: network stopped twice to work after around 3 weeks, host OS being RH. The same setup with host OS Ubuntu 16/18/20 *never* had any problem. I switched to virtio for this VM 2 weeks ago, will see what is the result.

Daniel

Hello Bob. We changed the cable from switch to ISP router, and we have much less problems. In the mean time I asked ISP to fix the floow to 1000/full instead of auto (already done on our side), don't know if they did it.

Concerning the virtual NIC, I would agree if *both* ISP links would have the problem as all the traffic is going out with the same NIC using VLANs. Can give a try to vmxnet3 if problem still persistent.

On another site from this customer I faced problem with one VM (Asterisk on Ubuntu 20.04) where the NIC was e1000: network stopped twice to work after around 3 weeks, host OS being RH. The same setup with host OS Ubuntu 16/18/20 *never* had any problem. I switched to virtio for this VM 2 weeks ago, will see what is the result.

Daniel

Ah, Daniel, I didn't realize you were working with Ubuntu instead of VMWare.

Cheers - Bob

My english so bad ?

For the original problem we really suffer less noise to not say (to early) zero after the cable change. Thanks for the hint !

Daniel

Hi. I confirm that from the cable change time, the flow of mails concerning up and down from this ISP drastically decrease. Next step will be to switch from e1000 to virtio driver for libvirt.

Thanks to all your help.