During February 2021, several members of the production IP Address Management appliance grid will be refreshed in-place with new hardware, and the geo-redundant backup grid manager appliance (used in disaster recovery scenarios and some planned maintenance scenarios, including this one) will migrate from University of Illinois IP space to a public IP in AWS.
As a consequence of this migration, ipam.illinois.edu will at times no longer be reachable from on-campus hosts which lack outbound Internet access (e.g. private IPv4 nets without NAT). Note that this change in reachability only affects the Grid Manager interface used by IT Pros, and will not prevent such hosts from obtaining DHCP leases or resolving DNS queries.
Action required: IT Pros should ensure that their use of ipam.illinois.edu (via the GUI or the API) to make DNS and DHCP configuration changes is always from a system which has outbound Internet access.
Detailed schedule:
On Tue Feb 9 between 5:00-7:00am, the two DHCP appliances will be replaced with new hardware (one at a time, to avoid interrupting service), and ipam2 (the backup for ipam.illinois.edu) will migrate to a public IP in AWS.
On Tue Feb 16 between 5:00-7:00am, ipam.illinois.edu grid management will be switched over to ipam2 (in AWS), and ipam1 (the primary, on campus) will be replaced with new hardware.
On Tue Feb 23 between 5:00-7:00am, ipam.illinois.edu grid management will be switched back to ipam1 (on campus). Note: at this time ipam.illinois.edu will again be reachable from on-campus hosts which lack outbound Internet access, but IT Pros should not rely on this going forward.
How will services be affected during the maintenance windows?
- During the maintenance windows, IT Professionals will not be able to log in to Grid Manager (via the GUI or the API) to make DNS and DHCP configuration changes.
- Any Scheduled Tasks created in Grid Manager that have not completed before maintenance begins will be automatically removed.
- Due to the use of DHCP Failover, clients will in general still be able to obtain DHCP leases. However, if a particular DHCP Range is very nearly full and experiencing a lot of churn (old clients leaving and new clients joining the network) during the maintenance window, it is possible that some new clients joining that range may not be able to obtain leases until both servers are back online.
- DNS query resolution is not impacted by this change.
Please contact hostmgr with any questions or feedback.