Unit 2 Assignment 1 DHCP Troubleshooting
Jeannette Jauregui
Mr. Tran - NT1330 Client-Server Networking II - April 3, 2015
Unit 2 Assignment 1: DHCP Troubleshooting
Attention Junior Admin: When PC’s are booted up, they automatically start looking for the DHCP server on the network. The server, once contacted sends out a message offering an IP address, subnet mask, default gateway, etc. The PC then essentially says back to the server, “ok, I got it”. At this point, the DHCP Server sends the ACK to let the PC know the IP address has been reserved and leased. This is done with every PC on the network, each time they are turned on. However, you have to keep in mind, the PC will not contact the DHCP Server again until halfway through whatever amount of time has been set for the lease time, IE: It will contact at day 4 using the default 8 day lease time. Being as you made the adjustments on Friday, some of the PC’s will not perform the above task until Tuesday, by default. What you need to do to correct the problem is force each of the PC’s that did not pick up the new leases from the scope to grab new IP addresses. This can be done by going to each PC, and in DOS, perform an “ipconfig /release” followed by “ipconfig /renew”. This will force the PC to renew its lease and grab a new IP Address. You may also want to look at your scope configuration to be sure the network and subnet masks match the router and it’s configuration on the LAN. However, in the future, I would suggest when making scope adjustments on a Friday, shorten the initial lease time to 2 days. This will make the PC’s automatically do the release and refresh over the weekend. Then when you return on Monday, you may then reset the default time to whatever you would like. Hope this helps,
IT Admin
Mr. Tran - NT1330 Client-Server Networking II - April 3, 2015
Unit 2 Assignment 1: DHCP Troubleshooting
Attention Junior Admin: When PC’s are booted up, they automatically start looking for the DHCP server on the network. The server, once contacted sends out a message offering an IP address, subnet mask, default gateway, etc. The PC then essentially says back to the server, “ok, I got it”. At this point, the DHCP Server sends the ACK to let the PC know the IP address has been reserved and leased. This is done with every PC on the network, each time they are turned on. However, you have to keep in mind, the PC will not contact the DHCP Server again until halfway through whatever amount of time has been set for the lease time, IE: It will contact at day 4 using the default 8 day lease time. Being as you made the adjustments on Friday, some of the PC’s will not perform the above task until Tuesday, by default. What you need to do to correct the problem is force each of the PC’s that did not pick up the new leases from the scope to grab new IP addresses. This can be done by going to each PC, and in DOS, perform an “ipconfig /release” followed by “ipconfig /renew”. This will force the PC to renew its lease and grab a new IP Address. You may also want to look at your scope configuration to be sure the network and subnet masks match the router and it’s configuration on the LAN. However, in the future, I would suggest when making scope adjustments on a Friday, shorten the initial lease time to 2 days. This will make the PC’s automatically do the release and refresh over the weekend. Then when you return on Monday, you may then reset the default time to whatever you would like. Hope this helps,
IT Admin