NETGEAR is aware of a growing number of phone and online scams. To learn how to stay safe click here.
Forum Discussion
GS728TP v1 failed update
Can you tell me if it's possible to restore the GS728TP v1 after a failed update?
The firmware was 6.0.1.14.
I updated to the latest firmware 6.0.1.30 via SCC (Smart Control Center).
SCC (Smart Control Center) reported that the firmware was updated and the switch would reboot.
But after this update, the switch keeps rebooting.
How can I restore it?
10 Replies
GS728TP v1 failed update
Can you tell me if it's possible to restore the GS728TP v1 after a failed update?
The firmware was 6.0.1.14.
I updated to the latest firmware 6.0.1.30 via SCC (Smart Control Center).
SCC (Smart Control Center) reported that the firmware was updated and the switch would reboot.
But after this update, the switch keeps rebooting.
How can I restore it?
Does pressing the reset button for 10 seconds change anything?
If the FW was applied correctly and acknowledged by the system and rebooted, something happened.
Might check with NG support and see if there are any thing they can help with.
I updated to the latest firmware 6.0.1.30 via SCC (Smart Control Center).
SCC (Smart Control Center) reported that the firmware was updated and the switch would reboot.While this isn't the root cause for this issue: The fine User Manual does from about 2012 - since first release more than a decade ago - not suggest using SCC. Only Web and FTP based uploads are supported.
How can I restore it?
Permitting TV bootloader was not destroyed, there might be some chance the bootloader falled back to tftp loading, probably due to a corrupted image load.
Probably the switch bootloader does fall-back to tftp, eg. due to a bad firmware image.
How can I restore it?
The switch reboots in about 70 seconds in a cyclical fashion.
At 30 seconds, the port LED lights up, stays on for 15 seconds, goes out for a while, comes back on, and then the switch reboots.
Instead of digging in the dark - connect the serial port pins on the switch motherboard. Pinout is similar on all Netgear devices
Accessing Bootloader via Putty on RBR50 | NETGEAR Communities
Alternate attempt is to connect from a computer in the 192.168.0.0/24 subnet, like 192.168.0.123/24 255.255.255.0, disconnect all switch ports from DHCP servers, and fire up a tftp application attemting to push the firmware image.
Alternate attempt is to connect from a computer in the 192.168.0.0/24 subnet, like 192.168.0.123/24 255.255.255.0,
FWI, the switch IP normally defaults to 192.168.0.239 when DHCP fails.
There are several connectors on the board, but they're not labeled. I couldn't find any information about the UART connector pin assignments for the Netgear Switch GS728TP V1.
Can someone tell me which UART connector and which pins are responsible for what?
Photo of the connectors on the board.
The image shared on ibb.com with the 2x5 pins reminds me more to a JTAG port. J2 with the notch on the 5x2 Dupont connector -might- be intended for plugging a RS-232 DB9 COM header cable designed for the mainboards with 2.0 mm pitch header pins. AT resp. Everex pinout.
- 5x2 Dupont connector, 2.0mm pitch
- AT/Everex pinout
I'd expect to find a an unpopulated 4-pin UART serial header on the motherboard (usually labelled as JP1, J3, or CONSOLE (wild guessing, JP1 or J1 most likely) near the main Broadcom SoC or flash memory).
The 4-Pin Internal Pinout
Netgear is highly consistent across their smart switch and router lines with their 4-pin internal layout. On the PCB, look for the square solder pad or the small arrow/number indicating Pin 1.
The standard pinout configuration runs as follows:
Pin Number Signal Name Description 1 VCC / 3.3V Power (Do NOT connect this to your serial adapter!) 2 RX Data entering the switch 3 TX Data exiting the switch 4 GND Ground reference Critical Connection Guidelines
- Voltage Warning (TTL Levels): This header operates at 3.3V TTL logic levels, not RS232 levels. Connecting a standard 12V RS232 serial cable or DB9 adapter directly to these pins will permanently fry the switch's motherboard. You must use a USB-to-TTL adapter (such as an FTDI, CP2102, or PL2303 chip breakout board) configured to 3.3V mode.
- Leave VCC Disconnected: Never connect Pin 1 (VCC) to your USB-to-TTL adapter. The switch is already powered by its internal power supply. Connecting the adapter's 3.3V or 5V power line to this pin risks creating a voltage conflict that can damage both the switch and your computer's USB port.
- The RX/TX Cross: When wiring your USB-to-TTL adapter to the board, remember that the signals must cross over:
- Adapter GND $\rightarrow$ Switch GND (Pin 4)
- Adapter TX $\rightarrow$ Switch RX (Pin 2)
- Adapter RX $\rightarrow$ Switch TX (Pin 3)
Serial Terminal Settings
Once connected, open your preferred terminal emulator (PuTTY, Tera Term, Minicom) and configure your COM port to the following standard Netgear settings:
- Baud Rate: 115200 (Some older revisions of the GS728T use 9600, but 115200 is standard for modern firmware bootloaders)
- Data Bits: 8
- Parity: None
- Stop Bits: 1
- Flow Control: None
If you power on the switch while connected, you should instantly see the U-Boot or CFE bootloader decompression text scrolling across your screen.
Thanks for the reply!
There is indeed a 4-pin connector on the board: 3.3V signal 1, signal 2, ground.
I connected an oscilloscope to it and saw that there's constant packet exchange on signal 1, and there's constant packet exchange on signal 2.
On other devices I've restored, packet exchange was only on one signal pin.
Here, packet exchange is constant on signal 1 and signal 2.
I'm not entirely sure that this is a UART connector.
There are photos of Netgear switch UART connectors online, and they are all 10-pin.
NETGEAR Academy
Boost your skills with the Netgear Academy - Get trained, certified and stay ahead with the latest Netgear technology!
Join Us!
