G+_Eddie Foy Posted September 5, 2015 Share Posted September 5, 2015 Looking for some advice. I'm changing my subnet (from 192.168.1.0/24 to 192.168.166.0/22 -don't ask why) I have most everything on DHCP on reservations. A few static IPs: router, 2 managed switches, WiFi AP, and 3 NAS's (one NAS is the DHCP server) Is there a painless way to change the statics? Or will a second temporary LAN as I change them manually be needed? (I'm ok with redoing the DHCP reservations, I've kept a good spread sheet of the LAN, and might be able to 'sed' the configs.) Link to comment Share on other sites More sharing options...
G+_Travis Hershberger Posted September 5, 2015 Share Posted September 5, 2015 Eddie Foy, are you building up to many networked projects? Anyway, the DHCP are easiest to change. After updated the DHCP server just release and renew the ip addresses, or in Linux ifdown/ifup the adapter. The statics aren't so easy to set. If you have at least one managed switch you could add a manual route to temporarily route between the two subnets. Not ideal, but it should work "till I get around to it". Link to comment Share on other sites More sharing options...
G+_Eddie Foy Posted September 5, 2015 Author Share Posted September 5, 2015 HEY! I said *DON'T ASK!!* :P (no, just conflicts with other test networks at times) Yeah, DHCP isn't much a prob. I have a very short lease time right now. I guess just budget a few hours, and man up. Link to comment Share on other sites More sharing options...
G+_Eddie Foy Posted September 5, 2015 Author Share Posted September 5, 2015 Oh, thanks. Link to comment Share on other sites More sharing options...
G+_610GARAGE Posted September 5, 2015 Share Posted September 5, 2015 Correct me if I'm wrong, but if your old subnet will be in your new subnet, could you not change your router, then update statics from a computer that resides in within the old subnet. Link to comment Share on other sites More sharing options...
G+_Eddie Foy Posted September 5, 2015 Author Share Posted September 5, 2015 Your right, if that was my set-up. 192.168.1.0/24 moving to 192.168.166.0/22 doesn't encompass the old 192.168.1.0/24 (if my math is right) And my DHCP server is not on my router, its on a NAS down stream. Router, NAS and switches all have static IPs. Makes this project a bit sticky, switches especially. Link to comment Share on other sites More sharing options...
G+_Travis Hershberger Posted September 5, 2015 Share Posted September 5, 2015 You'll just be without the internets for a bit. Shouldn't take that long to manually change the few static ip addresses. I got to do that at work this week after some storms took out a bunch of networking gear (for us, 2 switches is a bunch.) Link to comment Share on other sites More sharing options...
G+_Eddie Foy Posted September 5, 2015 Author Share Posted September 5, 2015 Can you make mods to Cisco IOS to the start config, leaving the run config alone? Then just reboot all 3 at once? Link to comment Share on other sites More sharing options...
G+_Ben Yanke Posted September 5, 2015 Share Posted September 5, 2015 Yeah, that might work! Link to comment Share on other sites More sharing options...
G+_Ben Reese Posted September 6, 2015 Share Posted September 6, 2015 It would add a few extra steps, but the statics could be changed to reserved + DHCP before the switch then back after the switch (or, when you get to it). Link to comment Share on other sites More sharing options...
G+_Micael Ebbmar Posted September 6, 2015 Share Posted September 6, 2015 If your current vlan is a SVI on a Cisco router, you can add a secondary subnet to the SVI to maintain connectivity e.g. int vlan 1 ip address 192.168.166.0 255.255.252.0 ip address 192.168.1.0 255.255.255.0 secondary After that it should be trivial to change the static addresses on the devices. Link to comment Share on other sites More sharing options...
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