我无法连接 WiFi。我可以看到网络，但无法连接。
事实
- 我可以看到不同的可用网络，但无法连接
- Ubuntu 18.04（内核 4.18）与 Windows 10 双启动
- Realtek 8821ae
- 联想 Ideapad 320
- WiFi 硬件在 Windows 10 上运行
我努力了
- 几乎所有关于这个主题和相关问题你都可以在这个论坛和其他论坛上进行谷歌搜索，例如 stackexchange
- 升级 Linux 内核
- 安装新驱动程序
- 更改为 WICD 而不是网络管理器
- 不同类型的网络，既有安全的，也有不安全的
从多种不同的方法中，我可以看到主要问题在于从 DHCP 服务器接收 IP 地址，因为 DHCPDISCOVER 仅返回任何内容或“未收到 DHCPOFFERS”。
有关该系统的一些信息：
$ sudo uname -a
Linux leon-Ubuntu 4.18.0-041800-lowlatency #201808122131 SMP PREEMPT Sun Aug 12 21:36:03 UTC 2018 x86_64 x86_64 x86_64 GNU/Linux
$ sudo lshw -C network
*-network
description: Wireless interface
product: RTL8821AE 802.11ac PCIe Wireless Network Adapter
vendor: Realtek Semiconductor Co., Ltd.
physical id: 0
bus info: pci@0000:01:00.0
logical name: wlp1s0
version: 00
serial: b0:fc:36:2b:a5:2d
width: 64 bits
clock: 33MHz
capabilities: pm msi pciexpress bus_master cap_list ethernet physical wireless
configuration: broadcast=yes driver=rtl8821ae driverversion=4.18.0-041800-lowlatency firmware=N/A latency=0 link=no multicast=yes wireless=IEEE 802.11
resources: irq:38 ioport:2000(size=256) memory:e8c00000-e8c03fff
$ lsmod | grep rtl8821ae
rtl8821ae 233472 0
btcoexist 155648 1 rtl8821ae
rtl_pci 32768 1 rtl8821ae
rtlwifi 86016 3 rtl_pci,rtl8821ae,btcoexist
mac80211 802816 3 rtl_pci,rtl8821ae,rtlwifi
$ ifconfig
wlp1s0: flags=4099<UP,BROADCAST,MULTICAST> mtu 1500
ether b0:fc:36:2b:a5:2d txqueuelen 1000 (Ethernet)
RX packets 0 bytes 0 (0.0 B)
RX errors 0 dropped 0 overruns 0 frame 0
TX packets 0 bytes 0 (0.0 B)
TX errors 0 dropped 0 overruns 0 carrier 0 collisions 0
$ wconfig
wlp1s0 IEEE 802.11 ESSID:off/any
Mode:Managed Access Point: Not-Associated Tx-Power=20 dBm
Retry short limit:7 RTS thr=2347 B Fragment thr:off
Encryption key:off
Power Management:on
$ iwconfig wlp1s0 essid <network>
$ dhclient -v wlp1s0
Internet Systems Consortium DHCP Client 4.3.5
Copyright 2004-2016 Internet Systems Consortium.
All rights reserved.
For info, please visit https://www.isc.org/software/dhcp/
Listening on LPF/wlp1s0/b0:fc:36:2b:a5:2d
Sending on LPF/wlp1s0/b0:fc:36:2b:a5:2d
Sending on Socket/fallback
DHCPDISCOVER on wlp1s0 to 255.255.255.255 port 67 interval 3 (xid=0x68e3751b)
DHCPDISCOVER on wlp1s0 to 255.255.255.255 port 67 interval 3
... etc
No DHCPOFFERS received.
No working leases in persistent database - sleeping.
$ dmesg # after network manager fails
[ 1283.623070] wlp1s0: authenticate with 68:72:51:42:67:36
[ 1283.623404] wlp1s0: send auth to 68:72:51:42:67:36 (try 1/3)
[ 1283.624978] wlp1s0: authenticated
[ 1283.630465] wlp1s0: associate with 68:72:51:42:67:36 (try 1/3)
[ 1283.642429] wlp1s0: RX AssocResp from 68:72:51:42:67:36 (capab=0x421 status=0 aid=2)
[ 1283.642726] wlp1s0: associated
[ 1283.643215] IPv6: ADDRCONF(NETDEV_CHANGE): wlp1s0: link becomes ready
[ 1329.024767] wlp1s0: deauthenticating from 68:72:51:42:67:36 by local choice (Reason: 3=DEAUTH_LEAVING)
[ 1329.064092] show_signal_msg: 29 callbacks suppressed
[ 1329.064095] dhcpcd[785]: segfault at 51 ip 0000559d9f6c26b0 sp 00007ffc2929e470 error 4 in dhcpcd5[559d9f6aa000+45000]
[ 1329.064102] Code: 85 e4 48 c7 44 24 14 00 00 00 00 48 8d 54 24 14 c7 44 24 1c 00 00 00 00 66 89 44 24 14 0f 85 d7 00 00 00 48 8b 87 b8 00 00 00 <44> 8b 28 48 8d 74 24 20 31 c0 b9 07 00 00 00 66 83 4b 06 04 48 89
[ 1329.440910] IPv6: ADDRCONF(NETDEV_UP): wlp1s0: link is not ready
$ dmesg | grep -i firmware
[ 14.517623] rtl8821ae: Using firmware rtlwifi/rtl8821aefw_29.bin
[ 14.517631] rtl8821ae: Using firmware rtlwifi/rtl8821aefw_wowlan.bin
$ rfkill list all
0: ideapad_wlan: Wireless LAN
Soft blocked: no
Hard blocked: no
1: ideapad_bluetooth: Bluetooth
Soft blocked: yes
Hard blocked: no
2: phy0: Wireless LAN
Soft blocked: no
Hard blocked: no
3: hci0: Bluetooth
Soft blocked: yes
Hard blocked: no
如果您有任何建议、更正或解决方案，我们将不胜感激。如果您需要从系统获取更多数据，请告诉我。