Posts Tagged ‘wireless network interface’

RaspberryPi Zero loses connectivity

Friday, July 9th, 2021

I have had a problem with RPI Zero. The system was working fine, and then it did not. I am using Raspbery Linux (Debian-based) with kernel 5.10.17+. Once a while (usually with network load) the system loses connectivity. Everything seems to be fine, if you have a serial/USB console there, but the wireless network fails. This problem was also mentioned here.

My workaround was to create a script with a cron scheduling. I have identified that the fault lies with the wlan driver, and it needs to get reloaded. So cron calls this script every minute, like this:

*/1 * * * * /usr/local/sbin/check_connection.sh

And the script (/usr/local/sbin/check_connection.sh) has this in it:

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#!/bin/bash
# DST is the network gateway
DST=192.168.230.1
if ! ping -c 5 -t 5 $DST > /dev/null
then
  #/usr/sbin/reboot
  /usr/bin/logger "Restarting wlan0 network driver"
  /usr/sbin/rmmod brcmfmac && /usr/sbin/modprobe brcmfmac roamoff=1
fi

Set this script to be executable, and your RPI Zero should work just fine. This is not a solution, but a workaround, of course, but it works well.

Orinoco_pci performance problems

Saturday, December 24th, 2005

Weird behavior of my Orinoco_pci wireless network interface. On my home 802.11b network, I get performance of about 600KB/s, instead of 1.1MB/s, which should be the approximate speed to expect to. Not only that, but browsing to external websites and the likes (I compare using wget), I get speeds of <7KB/s, and sometimes decreasing to a stall, on a 2Mb/s line. My desktop reaches speeds of >150KB/s, so I could either point at my wireless router/AP, or my wireless NIC. Using PCMCIA RTL8180 802.11b NIC, and using it with NDISwan drivers, I’ve got speeds of above 150KB/s, which points at my built-in Orinoco wireless interface.

I’ve tried downloading the newer orinoco driver, 0.15rc4 (instead of my existing 0.15rc2), and got similar results. I got stalled a bit later (testing with 18MB zip file), but it could be random point, just as well. Using the PCMCIA, it worked correctly *ALL* times. Pity. I will have to pay the “price”, regarding battery life, and extra accessories, regarding wireless for now. I might try this same test with some other router/AP sometime, when I get near one of those.