Comcast Static IP /30 Setup Help needed
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I am relocating my office (both Comcast business accounts) and I currently have a static ip with a pfSense firewall. Old office has ip a.b.c.33 / 30 and we set the pfSense up with IP a.b.c.33 and gateway a.b.c.34 . The new office we have been given Ip a.b.c.230 / 30 and was told our usable ip is a.b.c.229 . We also have a Cellular backup device between the Comast router and the pfsense. So my initial setup in the new office was pfSense wit IP a.b.c.230 and gateway a.b.c.229. Not working. We called support and they said tech made mistake our ip is a.b.c.229 and gateway is a.b.c.230. Reconfigured not working. Called support again and they were not sure and did not want to reconfigure our devices so here we are. I have since eliminated the cellular failover box from the equation and connected directly into wan on comcast modem. When laptop is connected to lan1 it gets a 10.1.10.1 iP and reverse IP lookup returns a.b.c.230 as internet facing IP address. pfSense still no access in WAN port but laptop can get out. I have two questions, 1) I think there a misunderstanding of our given IP/Gateway because I can ping (from home) a.b.c.230 but not a.b.c.229. If the convention is the same as old office gateway should the new gateway be a.b.c.231? Could the comcast static IP be set up improperly?
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re Cellular device, is that literally connected between, to both routers? Seems like that should be a second WAN on pfSense?
.229 and .230 should be the usable IPs there, check a subnet calculator. If you can ping the .230 from home with nothing connected that would be the Comcast router. Unless they screwed up and your IP is in use by someone else…saw that once. Try a traceroute to it or unplug the Comcast router and ping again.
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Yup if it's all static try running a pcap on WAN and see what's there. Try to ping the .230 IP from something external while running the pcap and see if that arrives or you see arp requests etc.
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Cellular Device was connected to WAN1 of Comcast Modem. We connected to Wan1 of Cellular device with no luck. Laptop in Lan1 of Cellular device got IP and and could navigate net. Our current working office set up is .33 /30 with .34 as our gateway. I think my 1st problem is to figure out what is truly my static IP and what is truly my gateway. From home ping attempts to my working setup: reach the .34 but not .33 . From the 10.1.10.1 (Lan) of working modem in office the reverse IP lookup returns .34 . From behind pfSense I can ping both (expected). The revers IP lookup is .33 . Going to new office now to troubleshoot. I'll post results. I think my new IP is .229 with gateway of .230 . Took pictures so all duplicate hardware are in the same ports.
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Solved: My intuition was correct in that the .229 /30 Static IP from Comcast is the pfsense IP and the gateway is the .230 IP . However we did have to follow this video to get access to the internet. https://www.youtube.com/watch?v=vnxSdg1sV4c . When laptop is connected on the Modem Lan (10.1.10.1) IP lookups reveal the Gateway IP (.230) but when behind the pfsense the ip lookup reveals the pfsense IP (.229) . I used ipchicken.com as my lookup tool. The video basically has you disable wifi, firewall, and LAN DNS on the modem. Once we did this we were routed correctly.
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@edgewater Ugh, that sounds like the tech made more than one mistake. ;)
Had one once replace a modem, leave, then we find out only one IP out of 5 is working. And, AND, the model of modem that actually supports multiple static IPs was no longer available. The new one "has problems with that." After a couple days they tracked down one more old model in a truck, and installed that.