I've been unable to connect to the SQL Server at my web host recently started about a week agoand I am beginning to suspect that Comcast is blocking traffic on some ports. I never had any trouble at all before, so this is really bugging me. Cosmotek is being pretty good about checking things on their end, but I also want to make sure it isn't on my end of things.
So, is there any way that I can check to see if Comcast is the cause of my troubles? Thanks Pete. Cable modem, and I want to know what to look for before I call them and ask them. I am running a Netgear MR router, and it never caused any problems before. I emailed Comcast tech support, let's see if I get an answer. Think they might be blocking portthe SQL port that propagates the Slammer worm? I got in touch with tech support and they assured me that they do not block any ports.
Is there any way to do a tracert of sorts, but on a given port, to see where the port gets blocked? There are 25 hops yeah, crazy, I know, and 5 of them are before Comcast's gateway between me and my web host's SQL server, so it's not going to be easy to figure out I'm at work so I can't check it out, but if it does work let me know, because I know I've needed something similar in the past.
Just curious, that's all. Yes, which is why it's important for me to get this fixed, since I have a bunch of work to do on it. SQL uses both and for communication. Some of our server folks thought the same way you did - then we got 30 infected servers that Saturday morning. What you can do to test a port is set up a service like FTP or HTTP on the port of interest, making sure to stop whatever might normally be using that port, then try to connect with the appropriate client, going to the port of interest.
If no connection, then something is blocking that port assuming you configured everything correctly. Using a unix utility called hping2 I determined that So it's not Comcast, it's verio who is blocking the ports. Since at least for me this router is 2 hops from your server, it's a problem on your web hosts, or their providers network. Your best bet is taking this problem up with your web host.
Hopefully they'll have a better solution then the security nightmare that directly accessing sql server directly over the Internet is.
In case any one cares here's the commands I used to determine this: hping2 -T -t 1 -p zeus. Verio is one of the big backbone providers, so they are likely the one blocking those ports. Many of the backbone providers blocked port after the Slammer worm UUNET didand probably added for good measure. How do I tell if Comcast is blocking traffic on a port? Thank you very much! Posted: Thu Mar 06, am. Posted: Thu Mar 06, pm. Posted: Fri Mar 07, am.Useable Static IP s are Thanks so much for taking the time to reach out to us through our business forums.
I can fully understand your need to ensure that ports you are using on your internal network are not blocked. Please be assured that the only ports that we block are listed within this web link. This will also explain why any ports listed may be blocked on our network. If you need any further assistance please don't hesitate to reach out to us at any time.
We configure powerful firewall and other utilty application on our servers to deny any un-authorized access and unauthorize use of our servers. Thanks for telling me about your situation. I'm looking forward to changing your experience to a positive one and working to get your connection port taken care of right away. Thank you for looking into the case. I am sorry I cannot find any email address or chat box where I could send you information.
Please provide guidence how I can send you private message. Hey there! Thank you so much for your patience. You would only need to send us a private message if we were going to discuss sensitive account information. After further research, I have discovered that port 25 and are blocked and cannot be lifted. However, I am seeing that port 80 and are not blocked so you should be good to go with those ports. Please let us know if you need any further assistance. Current Page. Comcast Business. Cart 0 Loading.
Shop Small Business. Sign In. Managing, controlling, and support for Custom Domain Names. Turn on suggestions. Auto-suggest helps you quickly narrow down your search results by suggesting possible matches as you type. Showing results for.
Search instead for. Did you mean:. New Contributor. Please Open Blocked Ports. All forum topics Previous Topic Next Topic.I use a VPN to connect to work. Lately I cannot connect at all.
Set Up Port Forwarding on Your Xfinity Gateway
No one is helping me other than sayings it's the other guys problem. Can anyone help me?
Thanks in advance! Go to Solution. I recommend that you make sure that the following ports, depending on your actual functional VPN operation, are open on your Comcast Gateway :.
View solution in original post. Thanks for the reply, however, I am extremely Tech-challenged. How do I do this? Need to know more about your interconnectivity to the NetGear for example: 1. Is your computer just plugged into one of the LanPorts ? Comcast only maintains downloading the correct boot file for your internet tier speed. All other technical hardware, firmware, etc.
Current Page. Comcast Business. Cart 0 Loading. Shop Small Business. Sign In.
Equipment Modems,Gateways.For the protection of the network and our customers, Comcast Business Internet blocks certain ports. Learn which ports are blocked and why. The ports listed below are blocked to protect against common viruses and worms, malicious intruders, and other security risks. These ports are blocked to protect our customers and the integrity of the Comcast Network; these blocks cannot be lifted.
Port 0 is a reserved port, which means it should not be used by applications. Network abuse has prompted the need to block this port.
DHCP ports can be used for malicious attacks, such as obtaining access to a computer or network and its devices. When improperly configured, they can expose critical system files or give full file system access run, delete, copy to any malicious intruder connected to the network.
In very rare situations, port 25 will be blocked by Comcast Customer Security Assurance on a per customer basis blocked at the modem and not across the network. This block will be preceded by an email and letters to the billing address. In this case, you can use secured port for sending email. If you are running a mail server please contact Comcast Customer Security Assurance at for more information on this block.
We may apply a sending block, which will prevent email programs or clients e. Customers may be advised by our Security Assurance team to switch their modem connection to a secured port that requires authentication such as port Current Page.
Comcast Business. Cart 0 Loading. Shop Small Business. Sign In. Equipment Modems,Gateways. Turn on suggestions. Auto-suggest helps you quickly narrow down your search results by suggesting possible matches as you type.Can anyone from Comcast help me by unblocking the por t 25 and let me know the reason that why it was blocked and how what can i do to prevent it from blocking agin.
We may apply a sending block, which will prevent email programs or clients e. Customers may be advised by our Security Assurance team to switch their modem connection to a secured port that requires authentication such as port You can find more information about the ports that we block through the following link:.
As for sending mails yes, we will use port but for incoming mails to our mail server we need port 25 so that our mail server can RECEIVE emails from other mail servers. Can you please reach out through private message with the name, address and phone number on the account? Thank you for supplying this information. I did check to ensure that we were not blocking port 25 on your end and we are not.
If we were blocking this port there are a few things to keep in mind. The only thing that would be impacted would be outgoing mail, not your incoming mail. We would also be blocking it on all IP addresses so a change of IP address is not going to assist in resolving this issue. The server is listing on IP of one of the static IP set, is it possible that on that particuler static ip has port block? Current Page. Comcast Business.
Cart 0 Loading. Shop Small Business. Sign In. Managing, controlling, and support for Custom Domain Names. Turn on suggestions.
How do I tell if Comcast is blocking traffic on a port?
Auto-suggest helps you quickly narrow down your search results by suggesting possible matches as you type. Showing results for. Search instead for. Did you mean:. New Contributor. Port 25 is blocked.This is a free utility for remotely verifying if a port is open or closed. It is useful to users who wish to verify port forwarding and check to see if a server is running or a firewall or ISP is blocking certain ports.
Port forwarding or port mapping allows remote computers to connect to a specific computer or service on a private network. This allows you to run a web server, game server or a service of your choosing from behind a router. When you forward a specific port on your router, you are telling your router where to direct traffic for that port. This utility can verify the success of that process. Please refer to your routers manual or manufacturer for assistance in setting up port forwarding.
Most residential ISP's block ports to combat viruses and spam. The most commonly blocked ports are port 80 and port Port 80 is the default port for http traffic. With blocked port 80 you will need to run your web server on a non-standard port. Port 25 is the default port for sending and receiving mail.
ISPs block this port to reduce the amount of spam generated by worms on infected machines within their network. Your IP:. Port to Check:. Check Port.It has nothing to do with the physical network hardware ports on your router, TV, consoles or computers. Ports are simply a way for your network hardware and software to organize information traffic. Think of reserved lanes on a road. The sidewalk is for pedestrians. There might be a dedicated bike lane. Carpool vehicles and buses have their own lanes too.
Ports serve the same function. One port might be used for receiving emails, while another carries file transfer requests, or website traffic. So these two port types use different network protocols. Which you can think of as distinctive sets of rules for how bits of information should be sent and received. Both port types are built on the fundamental Internet Protocol IP that makes the internet and home networks, well, work.
However, they are suitable for different applications. TCP, on the other hand, is more like making a phone call. UDP messages are generally broadcast over a network to anyone who is listening on the specified UDP port. This makes it perfect for housekeeping type messages that relate to running the network itself.
A little corruption in your Skype chat is far less important than low amounts of lag, after all. TCP is much more common than UDP and absolutely makes sure that all data is received free from errors.
There are a LOT of ports.
A port number can be anything from 0 to ! There are established standards and ranges, which helps us make sense of the noise. Ports are associated with some of the most important and fundamental network services.
This makes sense, since the lower-numbered ports were assigned first.