Flushing vCenter DNS cache

Run this command to restart resolver

systemctl restart systemd-resolved.service

Test with nslookup, if issue is still there continue
Run following command and check if 127.0.0.1 is listed as preferred nameserver
```
cat /etc/resolv.conf
```
Run following command and check name of service (most probably dnsmasq)
```
netstat -alnp | grep 53
```
Restart dnsmasq using:
```
systemctl restart dnsmasq
```
Again test with nslookup and verify that old cached entry is not present

Refer:

Anonymous