我有一台运行 Lubuntu 18.04 的旧 SONY Vaio PCG-FR285E 笔记本电脑。我认为我快要让网络接口正常工作了，但我找不到缺少什么（我的网络设置能力接近于零！）。
网络接口是：
$ lspci | grep Ethernet
00:0c.0 Ethernet controller: Realtek Semiconductor Co., Ltd. RTL-8100/8101L/8139 PCI Fast Ethernet Adapter (rev 10)
我知道硬件没有问题，因为我已经通过从 FOG 服务器的 PXE 网络启动安装了 Lubuntu。
我必须将 8139cp 列入黑名单，以便内核可以声明它：
$ lsmod | grep 8139
8139too 32768 0
mii 16384 2 usbnet,8139too
（usbnet 已启用，因为我使用智能手机通过 usb 共享互联网）
$ sudo lshw -C network
*-network
description: Ethernet interface
product: RTL-8100/8101L/8139 PCI Fast Ethernet Adapter
vendor: Realtek Semiconductor Co., Ltd.
physical id: c
bus info: pci@0000:00:0c.0
logical name: enp0s12
version: 10
serial: 08:00:46:b0:25:03
size: 100Mbit/s
capacity: 100Mbit/s
width: 32 bits
clock: 33MHz
capabilities: pm bus_master cap_list ethernet physical tp mii 10bt 10bt-fd 100bt 100bt-fd autonegotiation
configuration: autonegotiation=on broadcast=yes driver=8139too driverversion=0.9.28 duplex=full latency=64 link=yes maxlatency=64 mingnt=32 multicast=yes port=MII speed=100Mbit/s
resources: irq:9 ioport:1400(size=256) memory:e0000000-e00001ff
*-network
description: Ethernet interface
physical id: 1
logical name: enp0s16f3u1
serial: 06:b4:5a:78:a4:fa
capabilities: ethernet physical
configuration: broadcast=yes driver=rndis_host driverversion=22-Aug-2005 firmware=RNDIS device ip=192.168.42.159 link=yes multicast=yes
我必须在启动后手动启用该接口：
$ ifconfig
enp0s16f3u1: flags=4163<UP,BROADCAST,RUNNING,MULTICAST> mtu 1500
inet 192.168.42.159 netmask 255.255.255.0 broadcast 192.168.42.255
inet6 fe80::dd47:b63a:8e94:7e71 prefixlen 64 scopeid 0x20<link>
ether 06:b4:5a:78:a4:fa txqueuelen 1000 (Ethernet)
RX packets 131 bytes 11200 (11.2 KB)
RX errors 0 dropped 0 overruns 0 frame 0
TX packets 154 bytes 20243 (20.2 KB)
TX errors 0 dropped 0 overruns 0 carrier 0 collisions 0
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 116 bytes 9194 (9.1 KB)
RX errors 0 dropped 0 overruns 0 frame 0
TX packets 116 bytes 9194 (9.1 KB)
TX errors 0 dropped 0 overruns 0 carrier 0 collisions 0
$ sudo ifconfig enp0s12 up
[sudo] password for vaio:
$ ifconfig
enp0s12: flags=4163<UP,BROADCAST,RUNNING,MULTICAST> mtu 1500
inet6 fe80::a00:46ff:feb0:2503 prefixlen 64 scopeid 0x20<link>
ether 08:00:46:b0:25:03 txqueuelen 1000 (Ethernet)
RX packets 4 bytes 240 (240.0 B)
RX errors 0 dropped 0 overruns 0 frame 0
TX packets 3 bytes 266 (266.0 B)
TX errors 0 dropped 0 overruns 0 carrier 0 collisions 0
enp0s16f3u1: flags=4163<UP,BROADCAST,RUNNING,MULTICAST> mtu 1500
inet 192.168.42.159 netmask 255.255.255.0 broadcast 192.168.42.255
inet6 fe80::dd47:b63a:8e94:7e71 prefixlen 64 scopeid 0x20<link>
ether 06:b4:5a:78:a4:fa txqueuelen 1000 (Ethernet)
RX packets 131 bytes 11200 (11.2 KB)
RX errors 0 dropped 0 overruns 0 frame 0
TX packets 156 bytes 20505 (20.5 KB)
TX errors 0 dropped 0 overruns 0 carrier 0 collisions 0
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 118 bytes 9318 (9.3 KB)
RX errors 0 dropped 0 overruns 0 frame 0
TX packets 118 bytes 9318 (9.3 KB)
TX errors 0 dropped 0 overruns 0 carrier 0 collisions 0
但是，网络管理器显示“设备未管理”，而且肯定无法连接。我检查了电缆和宽带路由器是否正常，因为另一台笔记本电脑确实可以顺利连接。
更多信息：
$ dmesg | grep -e eth0 -e 8139
[ 0.048233] pci 0000:00:0c.0: [10ec:8139] type 00 class 0x020000
[ 3.549707] 8139too: 8139too Fast Ethernet driver 0.9.28
[ 3.550558] 8139too 0000:00:0c.0 eth0: RealTek RTL8139 at 0x(ptrval), 08:00:46:b0:25:03, IRQ 9
[ 3.761694] 8139too 0000:00:0c.0 enp0s12: renamed from eth0
[ 2570.826291] 8139too 0000:00:0c.0 enp0s12: link up, 100Mbps, full-duplex, lpa 0xC5E1
$ cat /etc/network/interfaces
# interfaces(5) file used by ifup(8) and ifdown(8)
auto lo
iface lo inet loopback
auto enp0s12
iface enp0s12 inet manual
我希望它能够工作，如果可能的话，可以在启动时自动运行。
非常感谢您的帮助！
答案1
成立。
只需编辑 /etc/NetworkManager/NetworkManager.conf，在“[ifupdown]”部分中设置“managed=true”。
然后重新启动。