@talormanda : is it a Wireless connection? Do you have multiple connections (Wired + Wireless) and if so are all of them affected?
Cheers
@ouroumov This is a wired connection that was flawless under the prior version of MATE to 16.04. I do have wireless but I did not check it. I certainly will.
Hi @talormanda,
try changing your software sources download location and updating again as there are several problems with the repo’s not syncing or something like that!. this may well help you solve your problem.
Update guide is linked above!. 
Thanks for the dmesg output. I see IOMMU stuff that I’ve heard cause a lot of problems in Linux.
Try adding/changing:
GRUB_CMDLINE_LINUX="iommu=soft"to “/etc/default/grub” and then run “sudo update-grub” and then reboot.
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Open Caja with the following command:
Press Alt + F2 and type:
gksudo caja
then open File System (on the left of Caja) > etc > default > grub and edit the file per @Dave_Barnes's tip!. Look at my pic below:
@Dave_Barnes It looks like mine was set to:
GRUB_CMDLINE_LINUX=""
Can you explain what this is? Did this change from the previous version of ubuntu? Because my PC never had issues up until 16.04. I’m going to change it later and test when I’m home.
Previous Linux kernels used a DMA bounce buffer (ie. iommu=soft was default). Current Linux kernels use hardware iommu if available. Hardware iommu support exposes many new problems.
@Dave_Barnes So this was a change just added in 16.04? If so, why use it if there are so many problems? Ick.
The iommu change has nothing to do with Ubuntu. The change is in the Linux kernel. The iommu is set up by the PC BIOS and then managed by the Linux kernel. There are currently 63 bug reports containing iommu at kernel.org. These types of problems are very hard to find and fix. See
https://bugzilla.kernel.org/show_bug.cgi?id=111781
@Dave_Barnes Sorry. Not trying to be pushy, just want to know if there was something that changed going to 16.04 that made this issue arise?
@Dave_Barnes Some sad news. I did the change and the issue still persists. Here is the dmesg log:
http://pastebin.com/ByZLrFwZ
What I got out of it:
Line 1101: [ 1.398961] alx 0000:03:00.0 enp3s0: renamed from eth0 Line 1320: [ 4.385627] IPv6: ADDRCONF(NETDEV_UP): enp3s0: link is not ready Line 1321: [ 4.386149] IPv6: ADDRCONF(NETDEV_UP): enp3s0: link is not ready Line 1322: [ 4.386917] alx 0000:03:00.0 enp3s0: NIC Up: 1 Gbps Full Line 1323: [ 4.387135] IPv6: ADDRCONF(NETDEV_CHANGE): enp3s0: link becomes ready Line 1345: [ 14.976666] NETDEV WATCHDOG: enp3s0 (alx): transmit queue 0 timed out Line 1379: [ 20.082081] alx 0000:03:00.0 enp3s0: NIC Up: 1 Gbps Full Line 1384: [ 34.979203] alx 0000:03:00.0 enp3s0: NIC Up: 1 Gbps Full Line 1385: [ 74.981457] alx 0000:03:00.0 enp3s0: NIC Up: 1 Gbps Full
The above says setting IPv6 to “ignore” fixes the issue…but why would that cause this? and what issues do I have turning that to ignore?
From your dmesg log:
Command line: BOOT_IMAGE=/boot/vmlinuz-4.4.0-21-generic root=UUID=d8f6d76b-4d0c-4b60-b4ed-83fde031d9dc ro quiet splash vt.handoff=7
I don’t see iommu=soft.
Did you paste the correct dmesg log?
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I did. I will try to play around with it again after work and see, but that is definitely the file and I did have it added because I just checked.
And did you run “sudo update-grub” after doing that?
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Did it. Looks different now.
[ 1.313084] alx 0000:03:00.0 enp3s0: renamed from eth0
[ 4.144147] IPv6: ADDRCONF(NETDEV_UP): enp3s0: link is not ready
[ 4.144509] IPv6: ADDRCONF(NETDEV_UP): enp3s0: link is not ready
[ 4.259453] alx 0000:03:00.0 enp3s0: NIC Up: 1 Gbps Full
[ 4.259716] IPv6: ADDRCONF(NETDEV_CHANGE): enp3s0: link becomes ready
So far so good. This is such a unique problem.
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Hi. My solution was.
After the install 16.04 the ethernet not work.
ethtool enp4s0 said Link detected: no.
I did the following
1- remane, write NAME = eth0 into /etc/udev/rules.d/70-persistent-net.rules
sudo pluma /etc/udev/rules.d/70-persistent-net.rules
NAME=eth0
2-edit /etc/network/interfaces, like this.
auto lo
iface lo inet loopback
auto eth0
iface eth0 inet dhcp
3- and write this comand line into the /etc/rc.local
sudo pluma /etc/rc.local
ethtool -s enp4s0 autoneg off speed 100 duplex full
I think the problem is in the auto-negotiation. In my case if in off the ethernet work.
Before this check that the module is loaded. I was. the driver also. But only these three steps worked.
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I just bump on this thread while looking for a solution for a similar issue.
My issue:
Quick question, are the above suggested solutions successfully worked? Are these also applicable to wireless connections?