Comcast Business Support Community

February 7 Firmware Upgrade Broke IPv6

Comcast did an automatic upgrade on Feb 7, 2024 to my business class modem. Following the upgrade, the modem is rejecting all incoming IPv6 packets except those that are ESTABLISHED,RELATED. I have both the IPv6 and IPv4 firewalls disabled in the settings, but the IPv6 firewall is apparently

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CGA4332 Static IPv6

All, I'm adding yet another thread on this topic, trying to get official guidance from Comcast Business regarding supported configurations. I have static v4 and v6 addresses, I have my network router set to use PD to get a /59 prefix from the Comcast supplied CGA4332 modem. My prefix changes whene

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CGA4332 Static IPv6

All, I'm adding yet another thread on this topic, trying to get official guidance from Comcast Business regarding supported configurations. I have static v4 and v6 addresses, I have my network router set to use PD to get a /59 prefix from the Comcast supplied CGA4332 modem. My prefix changes whene

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I'd like to know this as well. I don't understand the lack of feature parity between IPv4 and IPv6 on their CPE. Honestly, skipping the whole DHCP-PD setup and just specifying next hop for subnets inside the static /56 (even if the webui only allow

Do I have static IPv6 addresses?

For the first time, I logged into my Comcast Business account, went to the "Manage Services", "Internet", page, and noticed a link to "View Static IP", so I clicked on it.It brings up a page that not only shows the static IPv4 addresses I know very well, but also "Static IPv6 Information", which is

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Do I have static IPv6 addresses?

For the first time, I logged into my Comcast Business account, went to the "Manage Services", "Internet", page, and noticed a link to "View Static IP", so I clicked on it.It brings up a page that not only shows the static IPv4 addresses I know very well, but also "Static IPv6 Information", which is

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@flyingrobots I know this post is 5 years old, but it seems my modem (Cisco DPC3941B) with DOCSIS version 2.3.10.13_5.5.0.5 and Software image DPC3941B_4.12p24s1_PROD_sey I'm able to choose a /59 out of my /56 with the proper setup and static ipv4 a

IPv6 and passthrough mode

Hello all, I just spoke with a Comcast technical representative and they clarified that Comcast currently does not offer IPv6 addresses when a customer modem is in pass through mode as it requires DHCP enabled and managed on the modem and that passthrough is the demarcation line so it's on the cu

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IPv6 and passthrough mode

Hello all, I just spoke with a Comcast technical representative and they clarified that Comcast currently does not offer IPv6 addresses when a customer modem is in pass through mode as it requires DHCP enabled and managed on the modem and that passthrough is the demarcation line so it's on the cu

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Hello, I have the same setup as you. You will need to take your cable mode out of bridge/passthrough mode, and your "router" behind the modem has to do DHCPv6-PD and send a "hint". If your "router" doesn't support dhcpv6-pd functionality, y

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/59 prefix delegation block changed...

I have a /56 static on Comcast Business. Recently I had a cable modem issue (as determiend by comcast) and the cable modem was replaced. Everything is working, but I received a different /59 (still inside my /56) so I had to renumber several vlans! How do I keep this from changing

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DUID wasn't empty, so that isn't it....in any case it seems if I sent a prefix hint with the exact /59 I want out of my /56 that seems to work, at least from Mikrotik RouterOS 7.6

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/59 prefix delegation block changed...

I have a /56 static on Comcast Business. Recently I had a cable modem issue (as determiend by comcast) and the cable modem was replaced. Everything is working, but I received a different /59 (still inside my /56) so I had to renumber several vlans! How do I keep this from changing

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@DofTNet_Enterprises This actually worked perfectly for me. Thank you for digging into this! I tried this on OPNSense (22.7.6) and even did a release/reload (Interfaces -> Assignments) & got the same prefix. I left the script fie

For what it's worth, this is the sanitized dhcp6c.conf file that was generated on my OPNsense box: interface lagg0_vlan1 { send ia-na 0; send ia-pd 0; request domain-name-servers; request domain-name; script "/var/etc/dhcp6c_wan_script.sh"

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