I am trying to access some URLs for work, through a corporate VPN
Connecting to the VPN is fine and some sites resolve just okay.
But for some URLs I cant connect, or ping the address.
If I ask a colleague to nslookup and send me the IP address, I still cant ping the address.
However if I add the IP and base URL to my /etc/hosts it works just fine.
I have checked its not blocked by selinux or my firewall or iptables.
Im trying to understand whats happening, the IP is likely to change so I would like to not have to rely upon the static IP in the /etc/hosts

> cat /etc/hosts

127.0.0.1   localhost localhost.localdomain localhost4 localhost4.localdomain4
::1         localhost localhost.localdomain localhost6 localhost6.localdomain6

123.456.789.0 work-db.com

> cat /etc/resolv.conf 

nameserver 127.0.0.53
options edns0 trust-ad
search .

> iptables -L -v

Chain INPUT (policy ACCEPT 0 packets, 0 bytes)
 pkts bytes target     prot opt in     out     source               destination         

Chain FORWARD (policy ACCEPT 0 packets, 0 bytes)
 pkts bytes target     prot opt in     out     source               destination         

Chain OUTPUT (policy ACCEPT 0 packets, 0 bytes)
 pkts bytes target     prot opt in     out     source               destination  

with entry in /etc/hosts

> nslookup work-db.com
Server:     127.0.0.53
Address:    127.0.0.53#53

Name:   work-db.com 
Address: 123.456.789.0 

without entry in /etc/hosts

> nslookup work-db.com 
;; communications error to 127.0.0.53#53: timed out
;; communications error to 127.0.0.53#53: timed out
;; communications error to 127.0.0.53#53: timed out
;; no servers could be reached

even if the DNS server wasnt resolving correctly, my understanding is I should still be able to ping just fine.