Updating the Powerline adapters in my home network

I have blogged previously about a couple of problems with using Powerline adapters in my home network:

• ‘Waiting for 192.168.1.254…’ (Why I could not access a home hub’s management page)
• Powerline adapters and IPv6

As my NETGEAR XAV1301 (200 Mbps) Powerline adapters bought in 2012 apparently do not fully support IPv6, and as my NETGEAR XAV5221 (500 Mbps) adapters bought in 2016 are no longer manufactured either, I decided to invest in some new Powerline adapters that would guarantee IPv6 support. My Web searches did not confirm that the current models of NETGEAR Powerline adapters support IPv6, so I decided to try TP-Link Powerline adapters because the TP-Link Web site states that all current TP-Link Powerline adapters support IPv6. I wanted Powerline adapters for five devices (router, smart TV and three computers), plus the ability to use a mains plug on at least two of those (i.e. so-called ‘pass-through’ adapters). I also wanted to avoid buying different models, in order to minimise the possibility of any problems. TP-Link have a range of 600 Mbps adapters under the name ‘AV600’, so I plumped for two TP-PL4010 adapters (single Ethernet port per adapter), one TP-PL4010P adapter (single Ethernet port and one mains pass-through socket) and one TP-PL4020P (two Ethernet ports and one mains pass-through socket). These all use the Qualcomm Atheros QCA7420 Powerline chipset (which happens to be the same chipset used in my old NETGEAR XAV5221 500 Mbps adapters).

Like NETGEAR, TP-Link does not have a Powerline utility program for Linux, so I had to install TP-Link’s tpPLC utility program in Windows 10 running in a VM (virtual machine) in order to configure the four TP-Link adapters and set the ‘Powerline network name’ to avoid crosstalk with my neighbour’s Powerline adapters that use the factory default network name (‘HomePlugAV’).

Anyway, I got everything set up and working, but soon noticed that there were quite frequent dropouts of the connection to my router and the Internet. Some dropouts did occur when I was using the old NETGEAR Powerline adapters, but I was surprised to find that the performance of the new TP-Link adapters was much worse. The dropouts typically lasted a minute or two. This was annoying, to say the least.

I started searching the Web, and ‘TP-Link’ and ‘dropout’ occur together a lot. I had already disabled Power Saving Mode in the adapters, so knew that was not the cause. I happen to know someone who also uses TP-Link adapters, and he mentioned that he also experienced frequent dropouts. In addition to turning off Power Saving Mode, he had implemented a shell script on his machines to ping an Internet site periodically to try and keep the connection from dropping out, but this did not appear to make any difference. I wrote the script below to try the same thing, and it did not cure the dropouts either:

#!/bin/bash
#
# Script to try to keep the Powerline adapter connected to this machine
# from dropping the connection to the router
#
FIRSTPASS=1
PREVIOUS=2
while true
do
    ping -W 2 -c 1 8.8.8.8 >>/dev/null 2>&1
    STATUS=$?
    if [ $PREVIOUS -ne 0 ] && [ $STATUS -eq 0 ]; then
        logger "Ping successful: connection to Internet is up."
#        echo "Ping successful: connection to Internet is up."
    elif [ $PREVIOUS -eq 0 ] && [ $STATUS -ne 0 ]; then
        logger "Ping unsuccessful: connection to Internet may be down."
#        echo "Ping unsuccessful: connection to Internet may be down."
    elif [ $FIRSTPASS -eq 1 ] && [ $STATUS -ne 0 ]; then
        logger "Ping unsuccessful: connection to Internet may be down."
#        echo "Ping unsuccessful: connection to Internet may be down."
    fi
    PREVIOUS=$STATUS
    FIRSTPASS=0
    sleep 10
done

In my Web searches I came across a a thread in the TP-Link SOHO Community forums with a URL for a new version of firmware for TP-Link Powerline adapters that use the Qualcomm Atheros QCA7420 chipset. I learned from the TP-Link forums that the firmware in NVM (Non-Volatile Memory) depends on the chipset manufacturer’s chipset, not on the Powerline manufacturer’s adapter model, whereas the adapter’s PIB (Parameter Information Block) does change depending on the model (including the country). So I started searching online for a PIB file for the three models of TP-Link adapter that I am using, but I could not find them. However, the Linux open-plc-tools command ‘plctool‘ enabled me to read the PIB from each adapter and store it as a file:

user $ sudo plctool -i eth0 -p TL-PA4010P.pib <MAC address printed on the adapter>
user $ sudo plctool -i eth0 -p TL-PA4010_TV.pib <MAC address printed on the adapter>
user $ sudo plctool -i eth0 -p TL-PA4010_HOME-HUB.pib <MAC address printed on the adapter>
user $ sudo plctool -i eth0 -p TL-PA4020P.pib <MAC address printed on the adapter>

The Ethernet interface in the computer I used is named ‘eth0′, so change it accordingly. You can give any name to the PIB files.

It is also easy to find out the adapters’ MAC addresses and current firmware by using another open-plc-tools command:

user $ plcstat -t -i eth0

The TP-Link tpPLC utility for Windows also shows the firmware version. I was surprised to see that the firmware version was different in the three models I had just bought:

• TL-PA4010P firmware version: 1.4.0.20-00_401115_191120_901
• TL-PA4010 firmware version: 1.3.1.2141-00_401013_171025_901
• TL-PA4020P firmware version: 1.4.0.20-00_402114_191120_901

The command to update the firmware in an adapter using the NVM file I downloaded from the URL in the above-mentioned TP-Link Community forum thread and the PIB file read from the relevant adapter, is as follows:

user $ sudo plctool -i <interface> -P <PIB file> -N <NVM file> -R <MAC address of adapter>

For example:

user $ sudo plctool -i eth0 -P TL-PA4010P.pib -N FW-QCA7420-1.5.0.0026-02-CS-20200114.nvm -R 15:B3:D2:D8:5F:BA

I am fortunate in that the three models of TP-Link Powerline adapter I bought all use the Qualcomm Atheros QCA7420 chipset, so I could use the same NVM file for all four adapters that I bought. I only needed to repeat the command with a different PIB file for each adapter model. The plcstat command can be used to check that the firmware version is different from the factory original version:

user $ plcstat -t -i eth0

Actually, the tpPLC utility in Windows 10 also has the ability to upload an NVM file and a PIB file to an adapter, so, as I have tpPLC installed in a VM, I can use that instead to update firmware in my TP-Link Powerline adapters.

And what difference did upgrading the firmware in my new TP-Link adapters make? A big difference. There are no more dropouts; the connection is now stable and I no longer get interruptions while browsing the Internet. It’s a pity that TP-Link does not supply every chipset’s latest firmware file and every model’s PIB file on their support Web site so that users can update their Powerline adapters.