My RB-2011l running latest version of routerOS does succeed in getting a dhcp address from cable modem. I’ve tried getting a dhcp address from internal routers without problems, but so far I haven’t found a way to get a dhcp address from cable provider. I’ve tried changing the MTU and l2tmu.
So far I can’t get through the dhcp discovery phase.
Thx for your help.
??? Are you bridging or switching the ports?
I’m trying to run this on ether1-gateway on a vanilla configuration, I’ve disabled all personal tweaks.
Usually in DOCSIS systems, if you even get an IP address from the DHCP integrated in the modem, its gonna have a really low lease time (like 1 minute), and after that, when the modem bridges you into the DOCSIS network and the lease time expires, the providers DHCP will take over and assign an IP to you.
Have you tried manually releasing and renewing when the DOCSIS modem connects to the ISP?
Are you sure your ISP is not using PPPoE or something else (static IPs)?
If you plug your PC directly into the modem, are you able to pull a DHCP address from your provider? Are you power cycling the modem once you have your router plugged in?
I’m able to pull as many dhcp addresses from the provider as I like (within certain bounds). I’ve been requesting dhcp addresses from this providers with my current dd-wrt based router, linux systems, android devices, apple devices for the last 7 years. So far this works without any problems, even with multiple devices requesting dhcp addresses concurrently. It is only the mikrotik router that fails to receive a dhcp address for some mysterious reason. I understand your questions about power cycling the cable modem: this would have been handy given that I would only to pull one dhcp address from the provider, which is not the case. As for PPPoE: I don’t think so.
The dhcp lease times for the addresses are in the order of days not minutes. The multiple concurrent dhcp addresses setup was run by using a switch directly connected to the modem, without a NAT-ing router. So all the dhcp addresses were routable addreses.
There have been a few times when I have been connecting a MikroTik router to a cable modem that I have had the same sort of experience. For no logical reason at all, it just wouldn’t pull and address. There have been three things I have done to overcome this. This first was upgrading the software. Sometimes that helps, but honestly not very often. Next, I have tried putting the DHCP client on a different port. Sometimes that really does work. As last resort, I’ll swap out the router. There have been a couple of times that I replaced a brand new router with a brand new router and the second one worked. Its frustrating and I’ve suspected that the upstream provider had something wrong with their network, but I have never been able to validate that.
Sorry to resurrect this thread, but what rickfrey describes is exactly what I have been experiencing. I have multiple large residential deployments of MikroTik hardware running in DHCP client mode alongside Netgear DOCSIS 3.0 cable gateways which are running in bridge mode and I am noticing slow speeds, connection dropping in and out etc. If the MikroTik is removed, all returns to normal. Can anyone help with this?