Lost Wifi After Kernel Update

Issues related to configuring your network
recobb
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Joined: 2015/02/22 14:20:45

Lost Wifi After Kernel Update

Postby recobb » 2018/02/02 03:07:25

When I boot into the latest kernel that was just updated: CentOS Linux 3.10.0-693.17.1.el7.x86_64 7 (Core), I have lost my RTL8723BE adapter. iwconfig does not show any wifi adapters, although lspci does:

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[root@COSLaptop rec]# lspci -nn | grep -i net
01:00.0 Ethernet controller [0200]: Realtek Semiconductor Co., Ltd. RTL8111/8168/8411 PCI Express Gigabit Ethernet Controller [10ec:8168] (rev 10)
03:00.0 Network controller [0280]: Realtek Semiconductor Co., Ltd. RTL8723BE PCIe Wireless Network Adapter [10ec:b723]


Yum update shows everything up to date, with what I believe is the correct package:

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Installed Packages
Name        : kmod-rtl8723be
Arch        : x86_64
Version     : 0.0
Release     : 4.el7.elrepo
Size        : 377 k
Repo        : installed
From repo   : elrepo[code][/code]
Summary     : rtl8723be kernel module(s)
URL         : http://www.kernel.org/
License     : GPLv2
Description : This package provides the rtl8723be kernel module(s) built
            : for the Linux kernel using the x86_64 family of processors.


However, if I boot from the previous kernel in the list: CentOS Linux 3.10.0-693.11.1.el7.x86_64 7 (Core), then the wifi adapter is found and works.

Running with 693.11 (instead of 693.17), iwconfig now shows:

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wlp3s0    IEEE 802.11  ESSID:"DracoP2" 
          Mode:Managed  Frequency:2.437 GHz  Access Point: 00:18:39:DA:37:9F   
          Bit Rate=1 Mb/s   Tx-Power=20 dBm   
          Retry short limit:7   RTS thr=2347 B   Fragment thr:off
          Encryption key:off
          Power Management:off
          Link Quality=62/70  Signal level=-48 dBm 
          Rx invalid nwid:0  Rx invalid crypt:0  Rx invalid frag:0
          Tx excessive retries:0  Invalid misc:3   Missed beacon:0

and ifconfig -a shows:

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wlp3s0: flags=4163<UP,BROADCAST,RUNNING,MULTICAST>  mtu 1500
        inet 192.168.1.11  netmask 255.255.255.0  broadcast 192.168.1.255
        inet6 fe80::da5d:e2ff:fe30:7d3b  prefixlen 64  scopeid 0x20<link>
        ether d8:5d:e2:30:7d:3b  txqueuelen 1000  (Ethernet)
        RX packets 925  bytes 166870 (162.9 KiB)
        RX errors 0  dropped 0  overruns 0  frame 0
        TX packets 602  bytes 259191 (253.1 KiB)
        TX errors 0  dropped 0 overruns 0  carrier 0  collisions 0


wlp3s0 is missing from both commands when running 693.17 kernel

I could just continue using the older kernel, but that is not a satisfying answer. Any suggestions?

Thanks,

Richard Cobb

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TrevorH
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Re: Lost Wifi After Kernel Update

Postby TrevorH » 2018/02/02 07:24:53

Are you sure you even need to be using kmod-rtl8723be? The distro kernel supplies an rtl87233be module that says it supports your card.
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recobb
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Joined: 2015/02/22 14:20:45

Re: Lost Wifi After Kernel Update

Postby recobb » 2018/02/02 16:48:50

Are you sure you even need to be using kmod-rtl8723be?


Well, that was sure simple. Removing that fixed it. Thanks!

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TrevorH
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Re: Lost Wifi After Kernel Update

Postby TrevorH » 2018/02/02 17:46:27

Evidently ELRepo already know about this as the kmod package is no longer in ELRepo.
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