there seems to be a way to unbrick DVR through USB flash drive instead of uart connection with ttl adapter.
this info below was posted on another forum. any idea how I can use this same method to flash firmware and unbrick?
"
it is possible to hook into the boot process before the DVR software starts, by inserting a USB stick with a file named “autoexec.sh” in the root directory. I have used this to get rid of the default root password and to have the system start an NTP server to keep the time constantly up to date (something the DVR8-4550 will not do despite what the documentation says. My USB stick contains the following files:
autoexec.sh
#!/bin/sh
mount -t tmpfs tmpfs /tmp
cd /mnt/usb
[ -d /tmp/autoexecs ] || mkdir /tmp/autoexecs
cp autoexecs/* /tmp/autoexecs
cd /tmp/autoexecs
chmod 755 *.sh
./custom-inits.sh &
autoexecs/ntp-server:
pool.ntp.org
autoexecs/passwd
root:*:0:0::/root:/bin/sh
autoexecs/custom-inits.sh
#!/bin/sh
mount -o bind passwd /etc/passwd
sleep 30
/usr/sbin/ntpd -p
"
this info below was posted on another forum. any idea how I can use this same method to flash firmware and unbrick?
"
it is possible to hook into the boot process before the DVR software starts, by inserting a USB stick with a file named “autoexec.sh” in the root directory. I have used this to get rid of the default root password and to have the system start an NTP server to keep the time constantly up to date (something the DVR8-4550 will not do despite what the documentation says. My USB stick contains the following files:
autoexec.sh
#!/bin/sh
mount -t tmpfs tmpfs /tmp
cd /mnt/usb
[ -d /tmp/autoexecs ] || mkdir /tmp/autoexecs
cp autoexecs/* /tmp/autoexecs
cd /tmp/autoexecs
chmod 755 *.sh
./custom-inits.sh &
autoexecs/ntp-server:
pool.ntp.org
autoexecs/passwd
root:*:0:0::/root:/bin/sh
autoexecs/custom-inits.sh
#!/bin/sh
mount -o bind passwd /etc/passwd
sleep 30
/usr/sbin/ntpd -p
cat ntp-server"
