Intermittent network connection (44-50% ping loss?)

[Bermanator98]

So I posted on here a while ago, here's the link: https://forum.proxmox.com/threads/linux-noob-can-only-ping-localhost-nic-problem.31415/

I left it for a while, not touching my VM PC for about 2 weeks, until now. I booted up the system and ran a ping <IP> -t from my PC, which, left over ~10 minutes, gave me a 50% loss when I came back. I reinstalled, thinking maybe it would fix the issue... Nope. I can ping the PC, but it's very intermittent, getting a response a couple times, then a couple time outs. I posted on linustechtips.com where I gave some more info, such as nslookup and a screenshot of cmd. *NOTE:* I just did a tracert now and it was finished after 1 hop compared to the 7 hops shown in the linustechtips forum. Here's the link: https://linustechtips.com/main/topic/713180-proxmox-network-issues/

I'm using the latest version of Proxmox, 4.4, and using a PCI NIC, chipset is Realtek RTL8110SC. I highly doubt it's the motherboard as it was working fine when it was in my system a few months ago...

Any input / suggestions on this is greatly appreciated, as I am completely stumped...

Thanks!!


- Michael

 

[Denny]

In your earlier post you indicated that you switched from the onboard nic to one that you purchased separately while troubleshooting. It is unlikely that either device is the culprit (two failures don't usually happen at the same time) . So what pieces remain that are common to both? Chances are you reused the original cable and left it plugged into the same port of the switch. Change these items one at a time to identify which is the culprit. I would start with moving the cable from one port to another on the switch. If that doesn't solve the problem, change the cable out.

 

[Bermanator98]

In your earlier post you indicated that you switched from the onboard nic to one that you purchased separately while troubleshooting. It is unlikely that either device is the culprit (two failures don't usually happen at the same time) . So what pieces remain that are common to both? Chances are you reused the original cable and left it plugged into the same port of the switch. Change these items one at a time to identify which is the culprit. I would start with moving the cable from one port to another on the switch. If that doesn't solve the problem, change the cable out.

I have tried a new cable on the same switch port and the new cable on the switch port that my desktop runs on. Same thing. I'm wondering if Proxmox isn't liking my motherboard... I really can't think of anything else that would be causing this issue...

 

[Denny]

From here we go down the rabbit hole looking for trouble. It is possible that your motherboard is an issue but I sort of doubt it. Power supply? What do your 3.3v and 5v rails look like? Any chance of swapping either powersupply or motherboard for testing purposes?

 

[Bermanator98]

From here we go down the rabbit hole looking for trouble. It is possible that your motherboard is an issue but I sort of doubt it. Power supply? What do your 3.3v and 5v rails look like? Any chance of swapping either powersupply or motherboard for testing purposes?

Unfortunately I don't have any spares of either... The PSU is only about 3 weeks old, I bought it specifically for this machine...

 

[Denny]

This is a long shot but here goes, if you recently built this machine, have you double checked tightness on all connectors and verified all screws that might be serving as ground planes are tight?

 

[Bermanator98]

So I can 100% confirm it's not the network connection going into the PC. I have an old dual core Dell that I installed Proxmox on w/ the same USB and same configuration... Did a ping <IP> -t and the only failed ping was the first one, which is normal.

This is really confusing, no clue what part of the system is acting up :/