Arch Linux

Matt3o

Member

From: Firenze, Italy

Registered: 2007-09-13

Posts: 177

inconsistent and jumpy wired connection

I have two PCs with different HW both having inconsistent and jumpy wired connection on local network.

The network is configured on both with static IP with systemd-networkd. When I connect from one to another or to a file server (with debian) the connection seems to be working fine, but then it lags terribly for 5-10 seconds and then gets very fast again (to be lagging after few seconds). This on any protocol I tried (ssh, ftp, nfs, ...).

I know it's not a router/network issue because one of the two PCs had linux mint before and it was working fine.

any ideas?

Matt3o

Member

From: Firenze, Italy

Registered: 2007-09-13

Posts: 177

Re: inconsistent and jumpy wired connection

made more tests using NetworkManager instead of systemd but ended up with the same issues.

any help would be really appreciated. thanks

x33a

Forum Fellow

Registered: 2009-08-15

Posts: 4,587

Re: inconsistent and jumpy wired connection

Both have different network cards too? Can you reproduce the problem with the lts kernel?

Matt3o

Member

From: Firenze, Italy

Registered: 2007-09-13

Posts: 177

Re: inconsistent and jumpy wired connection

they have very different network cards, one is a very standard and well supported intel card.

I haven't tried with LTS, I'll try that.

Head_on_a_Stick

Member

From: The Wirral

Registered: 2014-02-20

Posts: 8,999

Website

Re: inconsistent and jumpy wired connection

they have very different network cards, one is a very standard and well supported intel card.

I'm not good at guessing games...

lspci -knn|grep -iA2 net

---

Jin, Jîyan, Azadî

Matt3o

Member

From: Firenze, Italy

Registered: 2007-09-13

Posts: 177

Re: inconsistent and jumpy wired connection

one is

Intel Corporation Ethernet Connection I219-V [8086:15b8] (rev 31)
	Subsystem: Gigabyte Technology Co., Ltd Device [1458:e000]
	Kernel driver in use: e1000e

another

Intel Corporation Ethernet Connection I217-V [8086:153b] (rev 05)
	Subsystem: ASUSTeK Computer Inc. Device [1043:859f]
	Kernel driver in use: e1000e

and one with

Intel Corporation I211 Gigabit Network Connection [8086:1539] (rev 03)
	Subsystem: Gigabyte Technology Co., Ltd Device [1458:e000]
	Kernel driver in use: igb

Last edited by Matt3o (2016-02-08 10:38:15)

Head_on_a_Stick

Member

From: The Wirral

Registered: 2014-02-20

Posts: 8,999

Website

Re: inconsistent and jumpy wired connection

Have you gone through the troubleshooting suggestions here:
https://wiki.archlinux.org/index.php/Ne … leshooting

---

Jin, Jîyan, Azadî

Matt3o

Member

From: Firenze, Italy

Registered: 2007-09-13

Posts: 177

Re: inconsistent and jumpy wired connection

Yes, I checked the wiki, I believe the only relevant bit is "swapping cables" and checking connections. Everything seems okay. If I boot from a Ubuntu liveCD everything seems to be working fine.

I explicitly disabled DHCPv6 since I had some errors in the journal, but that didn't help

Starting DHCPv6 client after NDisc timeout failed: Invalid argument

Head_on_a_Stick

Member

From: The Wirral

Registered: 2014-02-20

Posts: 8,999

Website

Re: inconsistent and jumpy wired connection

I believe the only relevant bit is "swapping cables" and checking connections

I was thinking of the TCP window scaling problem actually.

---

Jin, Jîyan, Azadî

Matt3o

Member

From: Firenze, Italy

Registered: 2007-09-13

Posts: 177

Re: inconsistent and jumpy wired connection

tried that as well, unfortunately that doesn't seem the case.

thanks for your help, really appreciated.

Matt3o

Member

From: Firenze, Italy

Registered: 2007-09-13

Posts: 177

Re: inconsistent and jumpy wired connection

Also tried LTS kernel and adjusting MTU and qlen. Still no luck... wondering what the hell is going on here.

Edit: also tried to disable IPv6 altogether

Last edited by Matt3o (2016-02-09 09:58:35)