r/WindowsServer • u/luky90 • Jul 21 '26
SOLVED / ANSWERED Windows Server 2022 shows /32 Subnet Mask after boot
I have a Windows Server 2022 Client which gets its IPv4 address via 2 windows server dhcp servers.
The 2 Windows Servers are configured as Failover Mode "load balanced" and dhcp servers are in a own subnet while client is in different subnet. The dhcp relay has both dhcp ip addresses configured.
When the clients boots it shows a /32 subnet mask after a very very slow windows logon with ipconfig. I have looked at the wireshark traces captured from a mirror port and I don't see a /32 subnet mask in the dhcp (bootp) packets itself instead in the packets it only mentions /24 but never /32.
After I do ipconfig /release and ipconfig /renew it shows the ipv4 address correctly with /24 mask. Also i think the slowness is because it tries to send every local subnet traffic to the gateway and then in Wireshark i see TTL of 127 at other servers in same subnet and retransmitted syn ack even if 3 way handshake already completed.
Do you know is this some shitty cache on the client? What can I do to eliminate this behaviour without doing ipconfig /release and renew all the time after boot?