Ttgjyuk

Upon bootup the network connection appears to be connected, for several reboots, I was shortly able to ping 8.8.8.8. However, I'm not longer able to do this. Then after logging in (<30 seconds) the network manager says the cable is disconnected. Unplugging and re-plugging the cable does not change this status.

The wireless connection is working.

I have previously used the wired connection in older versions of ubuntu (16.10 & 16.04) on this laptop, although I haven't tested them recently.

The network cable works with other computers.

The NIC device is a BCM5762.

Here is the output of ifconfig

 enp1s0: flags=4099<UP,BROADCAST,MULTICAST> mtu 1500
 ether 40:b0:34:09:9a:c0 txqueuelen 1000 (Ethernet)
 RX packets 91 bytes 54152 (54.1 KB)
 RX errors 0 dropped 1 overruns 0 frame 0
 TX packets 146 bytes 32104 (32.1 KB)
 TX errors 0 dropped 0 overruns 0 carrier 0 collisions 0
 device interrupt 36 
 lo: flags=73<UP,LOOPBACK,RUNNING> mtu 65536
 inet 127.0.0.1 netmask 255.0.0.0
 inet6 ::1 prefixlen 128 scopeid 0x10<host>
 loop txqueuelen 1000 (Local Loopback)
 RX packets 294 bytes 23870 (23.8 KB)
 RX errors 0 dropped 0 overruns 0 frame 0
 TX packets 294 bytes 23870 (23.8 KB)
 TX errors 0 dropped 0 overruns 0 carrier 0 collisions 0

wlp2s0: flags=4163<UP,BROADCAST,RUNNING,MULTICAST> mtu 1500
 inet 10.87.252.202 netmask 255.255.0.0 broadcast 10.87.255.255
 inet6 fe80::3260:ab36:9b89:9e58 prefixlen 64 scopeid 0x20<link>
 ether 7c:b0:c2:4e:13:d0 txqueuelen 1000 (Ethernet)
 RX packets 1247 bytes 1208923 (1.2 MB)
 RX errors 0 dropped 0 overruns 0 frame 0
 TX packets 881 bytes 160559 (160.5 KB)
 TX errors 0 dropped 0 overruns 0 carrier 0 collisions 0

Here is the output of lshw -C network

 *-network 
 description: Ethernet interface
 product: NetXtreme BCM5762 Gigabit Ethernet PCIe
 vendor: Broadcom Limited
 physical id: 0
 bus info: pci@0000:01:00.0
 logical name: enp1s0
 version: 10
 serial: 40:b0:34:09:9a:c0
 capacity: 1Gbit/s
 width: 64 bits
 clock: 33MHz
 capabilities: pm vpd msi msix pciexpress bus_master cap_list ethernet physical tp 10bt 10bt-fd 100bt 100bt-fd 1000bt 1000bt-fd autonegotiation
 configuration: autonegotiation=on broadcast=yes driver=tg3 driverversion=3.137 firmware=sb latency=0 link=no multicast=yes port=twisted pair
 resources: irq:36 memory:e0820000-e082ffff memory:e0810000-e081ffff memory:e0800000-e080ffff
 *-network
 description: Wireless interface
 product: Wireless 7265
 vendor: Intel Corporation
 physical id: 0
 bus info: pci@0000:02:00.0
 logical name: wlp2s0
 version: 59
 serial: 7c:b0:c2:4e:13:d0
 width: 64 bits
 clock: 33MHz
 capabilities: pm msi pciexpress bus_master cap_list ethernet physical wireless
 configuration: broadcast=yes driver=iwlwifi driverversion=4.15.0-23-generic firmware=29.1044073957.0 ip=10.87.252.202 latency=0 link=yes multicast=yes wireless=IEEE 802.11
 resources: irq:47 memory:e0d00000-e0d01fff

I had my network card get disabled after this morning's Ubuntu update. Rebooting the machine in Win10 the network card still works, so it's an Ubuntu configuration.

The way I solved it was the following:

sudo lshw -C network

This listed the "logical name" values:

logical name: enp8s0
logical name: docker0
logical name: enp0s29f7u7c4i2

I have a Dell T7400, so I know the device is a Broadcom NetXtreme BCM5754. Dell support provides no Ubuntu drivers, but you don't really need one. Somehow my ethernet device name was renamed.

sudo vi /etc/network/interfaces

Add the logical name to the end of the file:

auto enp8s0
iface enp8s0 inet dhcp

Finally, turn the interface on:

sudo ifup enp8s0

This is unhelpful. The file I have for 18.04.02 LTS says 'ifupdown has been replaced by netplan.'

I can't find a way for this thing to actually work. I suspect you have to define the netcard in the ridiculous yaml file [/etc/netplan/01-netcfg.yaml] and then define routing there as well (the man page uses an example but it's a bit tough to read the man page example AND edit the file when you have real hardware). Once all that is done, then you run [ip link set up enp2s0] or whatever your interface name is.

I can ping the card, but can't get to the default network because there is no route and no route policy out of the box (or it got deleted after I rebooted not realizing the cable was bad). It took a lot of googling to figure out how to even show the interface again. Who would even consider Ubuntu for anything important?

It's going backwards using yaml. Thanks ubuntu, thanks alot. Appropriate for stack overflow's April Fool's Day that's for sure. So much for upgrading from Ubuntu 8.

I've spent so much time trying to get 18.04.02 LTS to work that at this point I'm, going to have to consider an alternate distro (I'm running Ubuntu 8 LTS and it's solid, less the patch support). I initially had a bad hard drive connected, couldn't use the installer to fix the bad blocks (no fsck), had to end up booting to a much older linux distro to run badblocks on it. Which works great. Drive is usable again, no thanks to the installer.

What a waste of time. Guess I'll just go get CentOS and migrate to that. It's a shame, really. For a while there Ubuntu was good stuff.