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BeardedOne's profile

New problem solver

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17 Messages

Thursday, December 9th, 2021 11:36 PM

Slow upload on static IPs

I've been trying to pin down the cause of some machines having slow internet upload speed and I seem to have tracked it down to static IPs. Machines that get NAT addresses straight from the modem have good upload speed but everything that is assigned a static IP, either routers or individual machines, ends up with slow upload speed of about 9 Mbs, NATed connections straight from the cable modem get about 35 Mbs upload.

If I reboot the modem/gateway the speed returns but only for a short while.

Anyone have a clue as to why this might be?

Accepted Solution

New problem solver

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17 Messages

3 years ago

Well, if anyone's interested in the result... The tech was out and initially said it's not possible. The speed shouldn't depend on the IP and the tech I talked to on the phone didn't know what he was talking about.  He initially connected his laptop to the modem and used DHCP for the IP and everything was fine. He said it was a configuration problem on my end. 

He seemed ready to leave at that point but I explained about the static IPs having the problem and I insisted there was an issue. He then set up a static IP on his laptop, I gave him a free one to use. I guess that's not something he does very often. After it was setup he tried a speed test again and lo and behold, slow uploads!

For lack of any other ideas he gave me a new modem. The old one is less than 6 months old but maybe I wore it out. :)

Everything seems to be working again with the new modem, static IPs and all.  

I'm not sure what was the "root problem" as they say in my business. Maybe it had something to do with the ICFR or maybe not. I'm just glad it's working properly again!

So, in the future if someone says the speed shouldn't depend on whether it's a dynamic or static IP you can you can tell them about the Bearded One and his particular issue. :)

Recognized Contributor

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25 Messages

@BeardedOne,

Thanks so much for updating us here with your experience! 

I'm really glad to hear the fix ended up being something as easy as replacing the modem! 

 

Despite the fact that we don't hear this type of issue too often, I'll definitely keep this in mind just in case and I'm sure your update will greatly help any other customers trying to resolve similar issues too. :)

I no longer work for Comcast.

Official Employee

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36 Messages

Hello, @Joevitalee, I'm sorry to hear you had to spend so much time working on a fix but still didn't one. I'd love to take a look at your account and confirm the new modem is on its way. In order to get started can you please click the chat bubble in the top right corner and send a message to our "Comcast Business" handle? 

Official Employee

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21 Messages

Thank you so much! Appreciate the direct message. We are absolutely going to make sure that this tech visit is able to remedy this issue. I can assure you that our goal is that you are always able to have the highest confidence in our products and support. I would be frustrated with the intermittent connection as well, our team works from home and knows that a consistent connection is everything. 

Official Employee

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21 Messages

Very sorry for any confusion! I have a follow up setup on this for tomorrow to touch base. Thank you very much for all of your time and patience. You are a greatly valued member of our Comcast family. 

Official Employee

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35 Messages

3 years ago

Thank you for taking the time to reach out and being part of the Xfinity family. The upload speed isn't tied to dynamic or static Ips, you should be getting what you pay for no matter what kind of Ip you have. I'd be happy to take a look at your account to see if I can find a root cause for you. In order to get started can you please click the chat bubble in the top right corner and send a message to our "Comcast Business" handle?

New problem solver

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17 Messages

3 years ago

I don't see a chat bubble.  When I set the machine to use DHCP everything is fine but if I set a static IP the upload speed will drop considerably after a while. It happens with Windows, Linux and routers.  I'm a bit stumped myself. I've been doing this a long time and the setup hasn't changed recently. From my logs it appears to have started a few days ago.

New problem solver

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17 Messages

3 years ago

I found a chat bubble on the main screen but it says it is currently unavailable. I will call in to support tomorrow. I think I had enough of this for today. 

Official Employee

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35 Messages

No problem! Sorry we couldn't help in the way you needed today. If you need anything else after you reach out to the phone team please feel free to reach back out. 

New problem solver

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17 Messages

3 years ago

They are sending a technician out this afternoon. Apparently I have issues with ICFR errors on the transmission. They say the packets for a static IP are bigger than non static IPs due to the routing information. The bigger packets may have trouble sneaking through while the regular DHCP packets get through, usually. 


That's the theory, We shall see if it holds up. 

New Contributor

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28 Messages

2 years ago

I have this problem EXACTLY. Had tech look at it to no avail. It appeared a few weeks ago.
Rebooting the modem makes it work properly for 10 minutes. This feels like a packet shapper.
Getting VERY VERY frustrated. Below shows the cap appearing.

(edited)

New Contributor

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2 Messages

2 years ago

We have been having the exact same problem for months. I called Comcast several times. Opened many tickets. Waited for tier 2 to call back, just to find out the tickets were closed immediately after hanging up with support. We are an IT shop and our clients are also having the same exact problem, even after the modems are replaced. This is a wide-spread issue. Please add me to the list of people needing an answer.

Official Employee

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19 Messages

@user_d20806 Thank you for taking the time to reach out to us on our Business forums. Please send us a direct message with your full name, business name, full address, and phone number. By clicking the "direct messaging" icon in the upper right page of our forum page. Once you click on that, input our shared handle (Comcast Business) to send us a private message.• Click "Sign In" if necessary 
• Click the "Direct Message" icon in the top right corner
• Click the "New message" (pencil and paper) icon 
• The "To:" line prompts you to "Type the name of a person". Instead, type "Comcast Business" there 
• - As you are typing a drop-down list appears. Select "Comcast Business" from that list 
• - An "Comcast Business" graphic replaces the "To:" line 
• Type your message in the text area near the bottom of the window 
• Press Enter to send it

New Contributor

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2 Messages

They are not all the same tier but all the uploads should be 25-35 and they are all getting 1-2.

The sites I've been to and tested myself are all on the same style modem. I have not compared part numbers.

We have six sites that are actively complaining about it.

New Contributor

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28 Messages

We can verify 4 separate sites that seem to be locked at 10Mbit upstream. All on the same 300/35 rate.
Everything worked at each site before and all started showing problems between 11/15/2020 and 1/1/2022.

Contributor

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19 Messages

I understand you were having issues. Are you currently still having internet speed concerns? 

I no longer work for Comcast. 

New Contributor

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28 Messages

@Comcast_Ashley​ 
The problem does still exist. The spikes above 10Mbit below represent us either rebooting the modem or unplugging and replugging the ethernet cables to get a few minutes of extra upload speeds. Our backups haven't finished one time since 12/20/2022. Also we aren't alone I know 3 other businesses around our area with similar issues that all appeared around the same time. You had a bad firmware update in Q4 last year.


New Contributor

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2 Messages

2 years ago

I am currently suffering the worst Upstream issues I have ever encountered.

Upload speeds that go from 20Mbps to 0.08Mbps when under load on a Business Class service at a premium for over 10months, 5 modems, 10 technicians, 2 field service calls and help from Tier2 repair support since March

Texas Comcast management refuses to take ownership of the Problem.

The Problem is identified outside of the Office ... outside of closest pedestal, outside of closest node, and I can get no movement on getting a resolution to this service problem.

The service problem even presents itself when you remove the Office from the modem with all wifi off.

What needs to be done to get help with Quality of service issues when the Comcast Customer Service says we can help no further because upper management will not recognize this as a problem.

What needs to be done when the Comcast customer service rep suggest you contact the Better Business Bureau and the local Attorney General's office to get help with your problem.

"Core Values"

Comcast core values comprise “integrity, entrepreneurial spirit, respect, and giving back.” The culture of this company proves that it is a people-centered rather than a self-centered one. This is shown by the manner in which the company respects its customers and all stakeholders while delivering its services."

Where is the integrity in honoring the promise of reliable business class service and listening to your employees when they tell you the issue at a clients office is outside the office.

Comcast Where is your integrity to fix this?

12yr of loyalty to Business class service should count for something!

New Contributor

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1 Message

2 years ago

We are experiencing the same upload speed problem that started this week. Upload speeds ranging from 0.00 to .07 Mbps. We run our systems on the cloud so this has hampered the entire office's productivity. If I could get it up to 3 or 4 Mbps, we'd be in heaven even though it should be much higher. How do we fix this issue? 

Download speeds are not a problem.... ranges 80 - 250Mbps, just upload speed. PLEASE HELP!