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Incoming destination port 25 blocked on IPv6 only?

SOLVED
Trusted Forum Contributor

Incoming destination port 25 blocked on IPv6 only?

Working through enabling IPv6 on my postfix-based Linux mail server connected to a DPC3939B. I am successfully getting the 2601::/64 address on the mail server's WAN interface, and I am able to successfully connect and send/receive mail on v6 ports 465 & 587. but port 25 seems blocked. A telnet attempt to port 25 from another Comcast IPv6 address yields a timeout, and a packet trace on the mail server's WAN during that telnet attempt shows no traffic reaching the server. The server is using 1 of 5 static IPv4 addresses, and port 25 is NOT blocked on that. Thoughts?

Accepted Solution

Re: Incoming destination port 25 blocked on IPv6 only?

I have the same issue with IPv6 and an SMC router.  The IPv6 team is working on a fix in my situation they hope to have working this week, though I am not sure whether or not it's router specific.

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amessina
Occasional Visitor

Re: Incoming destination port 25 blocked on IPv6 only?

I have the same issue with IPv6 and an SMC router.  The IPv6 team is working on a fix in my situation they hope to have working this week, though I am not sure whether or not it's router specific.

Re: Incoming destination port 25 blocked on IPv6 only?

Yep we know about this issue and we are working on new bootfile's that will allow SMTP via IPv6..  I will post when we launch the bootfiles national..

Comcast_Tuska
Trusted Forum Contributor

Re: Incoming destination port 25 blocked on IPv6 only?

Great thanks for the quick reply

Re: Incoming destination port 25 blocked on IPv6 only?

The SMTP enabled bootfiles are going to removed from the field for the time being, we will be replacing with a bootfile shortly..

Comcast_Tuska
Trusted Forum Contributor

Re: Incoming destination port 25 blocked on IPv6 only?

and of course which one do i have.... the cisco

 

thanks for the info tho

Re: Incoming destination port 25 blocked on IPv6 only?


@train_wreck wrote:

and of course which one do i have.... the cisco

 

thanks for the info tho


I am working on the Cisco but we had an issue with the other bootfiles and had to roll them back..

Comcast_Tuska
Tnelsom
Contributor

Re: Incoming destination port 25 blocked on IPv6 only?

Comcast_Tuska:  Does this port 25 blocking occur on the Netgear router as well?

 

Thanks,

 

Thomas

Re: Incoming destination port 25 blocked on IPv6 only?


@Tnelsom wrote:

Comcast_Tuska:  Does this port 25 blocking occur on the Netgear router as well?

 

Thanks,

 

Thomas


Yes the bootfiles get rolled back, I will ask about when we will roll it back out again..

Comcast_Tuska
Geoff_Adams
Occasional Visitor

Re: Incoming destination port 25 blocked on IPv6 only?

Any movement on this? I'm currently stuck (trying to test a complex system that I plan to deploy in a data center) because of this problem. I'm using the Netgear cablemodem.

 

I hope I don't have to set up my HE tunnels again just to work around this issue.

 

- Geoff