I was scratching my head for an issue which i encountered in one of my customer place where it did not make logic while troubleshooting.
Then i posted my question on a online forum and got an answer in a minute which totally embarrassed me :) I was happy that i was able to communicate the question clearly that the guy answered in a swift.
Okay enough story, This was my question.
Hi Techs,
The subject may sound hyping the issue, but i am really baffled. Apologize for the essay!
1. Core switch - EX4200 Stack
2. Access Switch - EX3200 48 pts
Core switch has a IP helper pointing to a windows DHCP server. Access switch is nothing but a dumb switch with just VLAN configured for desktop and IP phone's. Everything is working normally - meaning, if i plug in a new IP Phone or PC or daisy chain IPPhone and PC, every device can get IP from appropriate VLAN's.
Last week, we tried connecting a PC to one of the free ports and it got an IP address from DHCP server and life was good. When i wanted to change the IP address in the same subnet to a different IP statically, I lost connection to default gateway and even the LAN segment from that PC. Tried 2 different PC's - same result.
1. In PC, When i assigned static IP which was originally assigned by DHCP, it is working
2. When i assign static IP with different unused ip in the same segment, no reachability to even peers connected to same switch
3. When i 'reserve' the unused new IP in DHCP server with the PC Mac address, I receive the unused IP from DHCP server and everything is working good.
Any insight is much appreciated.
Regards
Balaji M
Answer in probably 2-3minutes time
@mellowd
Certs: 350-001, CCNP, CCIP, JNCIA-EX
Are you sure DHCP snooping isn't configured?
I checked and Yes, DHCP snooping was enabled for that particular data VLAN. Lesson learnt. For more info on Juniper DHCP snooping, below given is the article.
Regards
Balaji M
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