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Modem Upgrade Docis 3.0 to Docis 3.1

pete_c

Guru
Upgrading my Arris SB6190 3.0 Docis modem (X2) to an Arris SB8200 3.1 Docis modem tomorrow.
 
Wanting to write my experience with the upgrade relating to XFinity.
 
BTW since the beginning of cable internet have always purchased my modems and never have leased any equipment from the ISP provider.
 
Purchased it from Amazon.  Been using the Arris SB6190 (x2) for about 3 years now and its been working fine.
 
I asked XFinity today if I could do this for a week or so before committing to the new modem.
 
Two home configuration is identical....
 
Modem ==> PFSense (2 WAN and 4 LAN interfaces)
==> managed L2 switches (soon to be L2/L3 switches) and Ruckus WAP
 
Will post my procedure / process here...should be easy...it was when I upgraded the SB Modem last time.
 

LarrylLix

Senior Member
With cable (here) we share a small neighbourhood of users on one cable drop. The available speed is the loop speed divided by the user count.
I had a DOCSIS 3.0 and migrated to a 3.1 recently and this caused many more hiccoughs and data blips. AFAICT the receiving modem has a problem sorting out older modems signals and later tech signals on the same loop. This may clear up later once all users upgrade and that means that most will likely be offered deals to dump their old modems....maybe.
 
The length of cable and connections inside the home suddenly seems to be of concern and it was recommended I remove about 40 feet of cable between my demarcation point and the modem, when I had worse problems. I did find a reported gain of about 1 dB difference and it saved an older splitter connection also. Unless you have the latest high tech connections they are not rated at the 3 GHz they require. I never figured that little difference made any difference but perhaps just wiping the oxide off connections by twisting made some difference also. Of course, this time I also tightened down the ground rings with a wrench for non-finger removal.
 
My 3.0 modem was perfectly capable of handling the speeds I contracted but Rogers Cable wouldn't allow over 30 Mbps on the 3.0 modem????? That was the basis of my logic for the neighbourhood loop compatibilities thinking.
 
Good luck with the 3.1. There is a lot of BS about bad chipsets that was never based on anything...maybe just competitor propaganda.
 

pete_c

Guru
Just got confirmation from XFinity that I can activate the new modem with an XFinity app so I can do this tomorrow and leave the old modem registered.
 
More than likely when I bring up the modem the firmware will be upgraded as this is what happened when I installed the SB6190 which I have had no issues with now for around 4 years.  
 
Personally always used Motorola Sb modems (have a box full here) and never have had any issues with any of them.  In the old house XFinity replaced a 5 year old coax connection to my home with RG11 cable which they did and I did not have any issues with my connectivity.  (it was over 300 feet to the box though).
 

Frunple

Active Member
I upgraded to the same SB8200.
Xfinity sent the wrong boot file to it, they sent the extreme and it should've been the extreme pro, and they then could not get the correct file to it.
Went around in circles for weeks trying to get it fixed and every time resulted in the same thing.
The tech started by saying "That's not the correct boot file." and after hours of trying to fix it they ended by saying "You have the correct boot file."
Even though I was only getting 400M (Extreme) and not 800M (Extreme Pro) which I should've had.
 
I decided to get rid of Xfinity and had Frontier install a symmetrical Gig over fiber and have had zero problems with it. And no more dealing with idiots from Xfinity!
 
I also then tried to use the SB8200 to upgrade a friend on Xfinity and they couldn't get it to work. Pretty sure Xfinity bricked the brand new modem.
 

pete_c

Guru
First attempt to upgrade didn't work.  Wrote to Amazon and getting replacement tomorrow.  It just kept rebooting.  
 
I read about XFinity not seeing Docis 3.1 modems too well.  Lets see what happens with new modem.
 
In FL had Verizon FIOS for many years.  Verizon sold the accounts to Frontier.  It was a no contract Verizon account.
 
Frontier slammed my account when I wouldn't upgrade /sign a new contract.
 
I opened up a FL State Attorneys complaint.  Frontier fixed my Internet after the complaint was filed.  Guessing that they did this with many folks.
 
I then switched over to Comcast there.
 
Here in the Midwest I have the choice of using AT&T or Comcast.  I have been using Comcast for Internet now since the beginning of their cable internet in the 1990's.  I have a no contract account with them today.  ATT will not let me use my own equipment.  I still also use Direct TV for TV (no contract account).  
 
It would be great to get fiber here in the Midwest.  
 

pete_c

Guru
Just got this from an XFinity tech...
 
I completely understand and we are aware of that modem's capabilities, however, after our increase to the Gigabit speed from 1.0 Gbps to 1.2 Gbps, the firmware is no longer compatible. Our engineers are aware and working to correct the bootfile and firmware so everyone plays nice because we know that's a very popular model, but right now, it isn't compatible.
 
So returning the new modem when I get it.
 

pete_c

Guru
Well got a new Arris SB8200 yesterday from Amazon.  Installed it this morning with no issues.  Will give it a try for 30 days or return it to Amazon if it doesn't work for me.
 

pete_c

Guru
Got a new non contract price with paper billing and no auto debit for about $20 more for Gb.  Might give it a try.
 

pete_c

Guru
01, July, 2021
 
Noticed over the last week that the Arris SB8200 is not stable.  Failover to the LTE modem has occurred a few times now and I see odd errors in the modem event logs and RTT times spike then the PFSense firewall fails over.
 
Good that I purchased the modem from Amazon.  Most likely will switch back to the Arris SB6190 modem next week.
 
I have read good things about the Motorola Docis 3.1 sister modem.  
 

LarrylLix

Senior Member
pete_c said:
01, July, 2021
 
Noticed over the last week that the Arris SB8200 is not stable.  Failover to the LTE modem has occurred a few times now and I see odd errors in the modem event logs and RTT times spike then the PFSense firewall fails over.
 
Good that I purchased the modem from Amazon.  Most likely will switch back to the Arris SB6190 modem next week.
 
I have read good things about the Motorola Docis 3.1 sister modem.  
Maybe do some reading over at https://www.dslreports.com
 

pete_c

Guru
Thanks Larry.  Funny how hard XFinity pushed me to upgrade to Gb.  I pushed back telling them baby steps if the modem cannot deal with Gb.
 

LarrylLix

Senior Member
pete_c said:
Thanks Larry.  Funny how hard XFinity pushed me to upgrade to Gb.  I pushed back telling them baby steps if the modem cannot deal with Gb.
Yeah. My jump was from 30mps d/l up to 75 Mbps d/l. If I still had my old modem I think I may go back to 30 Mbps as I find much of the Internet doesn't support that speed at times of the day and I never needed that speed, adding up my appliance speeds. However I have found the streaming apps (Netflix, Prime etc..) use the maximum speed in small bursts to average a max. of about 10 Mbps or less anyway.
 
I believe I am finding Internet speed problems between USA and Canada when I compare streaming across the border during VR sessions with HD movies. Most of the US users see no pixelation whereas in Canada it is random full speed and pixelation and audio hiccoughs. I can't see a way to test via another ISP at the moment to see if it is ISP related or border crossing chokes.
 

pete_c

Guru
Really don't need the speed here either as only streaming movies one at a time and there is only two of us.  I do copy files / movies over to house #2.  Same service there and limited by the upload speeds of 6-10 Mbs anyhow.  Currently copying a 2.4Gb directory over and time wise it is taking around 20 minutes which isn't too bad.  Using OpenVPN server on the PFSense box and Linux OpenVPN client.  It does seem faster to run OpenVPN than it does to run IPSec VPN.
 
Way back when having issues with my wire here tested using the DSL Reports SmokePing for some 5 days.  XFinity did replace the underground cable to the outdoor box twice.  First time it was working great until it got buried then performance dropped.  Next new cable worked fine after it was buried.  Guessing first person that buried the cable also damaged it. 
 
DSL Reports / SmokePing use global servers such that you can see differences maybe?  
 

pete_c

Guru
July 12, 2021 - Update
 
Still testing Arris SB6190 modem.  I have until July 27 to test or return to Amazon.
 
Looks like the errors and disconnects on the modem were related to too high of signal levels.  This is the same issue I had with the Arris SB6190.
 
A couple of months ago noticed that my VOIP lines (4) kept dropping and I blamed those issues on Ooma / Obi (GV) and did not pay attention at the time to the modem and or PFSense.  PFsense kept sending me disconnect messages and failover messages.  Initially an XFinity forum tech had me put an attenuator on the line to the modem and that sort of worked.  (6 Db attenuator).  Note the cable went from the outside of the house to the modem some 15 feet in the Leviton panel in the basement.  Still having problems had a tech visit and he replaced the cable from the house to the outside box (~ 150 feet or so).  All was fine until the cable was buried.  Then again the modem kept bouncing.  Had another tech visit and said 2 techs said that there was nothing wrong with the cable.  Modem kept bouncing.  Next tech visit the cable was again replaced and XFinity tech removed suggested attenuator and installed a splitter with attenuation.  The modem didn't bounce any more.  One week later the line was buried and the modem continue to work fine.  XFinity sort of admitted that who ever buried the line damaged it.
 
Next here decided to upgrade the Arris Modem SB6190 to an Arris Modem 8200.  Purchased it from Amazon.  First modem didn't boot up such that I sent it back to Amazon.  Next modem booted up fine except that it would disconnect from the internet randomly 1-2 times a day.
 
Last Friday July 9, 2021 morning added my 6db attenuator.  (IE: total attenuation was now 12DB).  It worked.  I have not had an issue now since last week.  No failover or disconnects.  
 
Before adding attenuator:
 
Downstream power levels were averaging around (with one 6db attenuator)
 
+4-6 dBmv
 
After adding second attenuator (for a total of 12db attenuation) downstream power levels are averaging.
 
-0.5 dBmV
 
Upstream power levels now are around 45.0 dBmV.  I do not recall what they were before the attenuator add.
 
So now letting it run for another week or so to see how it does.
 
Concurrently looking at the Arris SB6190 in house #2.  There have not had any issues.  There is no attenuator on the wire and downstream signals are at around zero dBmV.
 
Next swapping out Arris SB6190 in house #2 to an Arris SB8200 and moving back up NAS (hot spare #2) to house #2 and seeing how it does.
Infrastructure in house #2 is identical to here.  IE: SB6190 ==> PFSense (Qotom box) ==> managed POE switch and Ruckus WAP.
Automating in house #2 using Tasmota WiFi switches, Ring Alarm, Amazon devices (now 5 there).
 
Finally going to Gb in the two homes if everything works using the SB8200 Docis 3.1 modem.    There are two Gb ports on the SB8200 with a configuration for LAGG to combine the ports to push it above 1Gb.  (specifically XFinity Gb service is 1.2Gb).  I am fine with Gb only and will test the LAGG configuration on the modem and the managed switch there and here.
 
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