Show dhcp6c status for ISP prefix
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I'm not quite sure what you're asking. Are you referring to getting temporary prefixes? If so, there is one option to check. It's System / Advanced / Networking / Do not allow PD/Address release. You want to select that. However, not all ISPs respect that setting.
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@JKnott said in Show dhcp6c status for ISP prefix:
Are you referring to getting temporary prefixes?
Yes! German Telekom does not assign anything fixed and Iam not sure if they would respect your mentioned setting. I read of that setting a few times but Iam unsure. However, the Fritz!Box shows some lifetime info for my current assigned prefix. And I wonder how it manage to do that and if pfSense could show such information as well.
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In addition: I know, that Telekom gives an /56 prefix. The Fritz!Box also shows that part but I dont see this information anywhere inside pfsense. Even the dhcp6c logs does not mention anything about a /56 prefix or if my "wish" for an 56 prefix was respected.
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@KluthR said in Show dhcp6c status for ISP prefix:
Even the dhcp6c logs does not mention anything about a /56 prefix or if my "wish" for an 56 prefix was respected.
Activate this one :
Now the Status System Logs DHCP will contain extra info.
Like :
I presume pltime is 10 minutes = the lease time. Pretty short if you asked me, but the prefix and upper IPv6 address didn't change for me the last 14 months.
When you ask for a /56 this doesn't mean the dhcp6c client is going to ask ask 256 * /64 = /56 = 256 prefixes from upstream.
It asks (only) a /64 prefix for every LAN interface where you've set :
You can see such a prefix here :
I know, not really "all the info in one nice place".
And oops : forgot about
Btw : These DHCP6 leases should may last 10 minutes or one hour or even more. This doesn't matter.
What matters is : that your ISP (or the ISP box, just 2 feet away from me) gives always the same prefix(s) and that the upper part of your IPv6 /56 stays the same also. If not, your devices can/will change their GUA regularly , and that pretty broken. -
@Gertjan said in Show dhcp6c status for ISP prefix:
Pretty short if you asked me, but the prefix and upper IPv6 address didn't change for me the last 14 months
Do you have the "Do not allow PD/Address release" enabled?
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Noop.
See image posted above.I don't 'need' that I guess, as it is my 'ISP Box' that handles the prefixes, and it it allocate to the same device = pfSense, as it is using the same DUID, the same prefixes over and over.
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@Gertjan said in Show dhcp6c status for ISP prefix:
Noop.
See image posted above.Sorry, missed that.
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@KluthR said in Show dhcp6c status for ISP prefix:
Yes! German Telekom does not assign anything fixed and Iam not sure if they would respect your mentioned setting.
Well, there's one way to find out. Enable it and see what happens.
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How have I to imagine this function? If the PPPoE disconnects for whatever reason, dhcp6c does NOT send a PD release. So after PPPoE reconnect, I get the same prefix? Does my ISP takes note what prefix I had?
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None of use are working for your ISP ^^, and I'm not aware of any FAQs, documentation, but you could find it out.
See my post above : set dhcp6c debugging mode on, and check the logs.
Answer can be found in the logs.
Like : did I get the same prefix ? -
@JKnott said in Show dhcp6c status for ISP prefix:
Well, there's one way to find out. Enable it and see what happens.
For the record: My ISP (German Telekom) does NOT respect the
Do not allow PD/Address release. I enabled it, saved, rebooted pfSense and I got another prefix.If this was the right way to test it.
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Hate to advocate for an ISP, or worse, an unknown ISP, but to their defense : if you (they) use PPPOE, and all traffic - IPv4 and IPv6 goes over this PPPOE Tunnel, and this pppoe tunnel gets shut down before any "hey, please, Do not allow PD/Address release" can get send : it will never reach them.
Also : I can image that ISPs treat "IPV6 addresses" as "IPv4 WAN addresses" : on any connect, you get another one. Many clienst just love that. Others hate it. And for xx ^$ a month you get a semi static IPv4 .... maybe this will also be the case for your IPv6 needs.
AFAIK : this shouldn't be done like that by your (my) ISP : they are breaking some IPv6 RFCs for sure.Actually, me just thinking out-loud here : is pppoe still a thing these days ?
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@Gertjan said in Show dhcp6c status for ISP prefix:
"hey, please, Do not allow PD/Address release" can get send : it will never reach them
Its the other way round: dhcpv6c sends an "Hey, please release PD" when it exits. The mentioned setting is avoiding it, so my ISP does not get any info to release it which should result in a "static" prefix.
@Gertjan said in Show dhcp6c status for ISP prefix:
is pppoe still a thing these days ?
Seems so. (VDSL2).
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@KluthR said in Show dhcp6c status for ISP prefix:
Its the other way round: dhcpv6c sends an "Hey, please release PD" when it exits. The mentioned setting is avoiding it, so my ISP does not get any info to release it which should result in a "static" prefix.
for this - what I meant to say.
The release doesn't get send .... or is discarded by the ISP anyway. -
@KluthR said in Show dhcp6c status for ISP prefix:
If this was the right way to test it.
I suspect it might take another reboot. However, the way I found out about the problem was just disconnecting & reconnecting the Ethernet cable to the cable modem was enough to cause the prefix to change.
