SOLVED: Reverse dns issues bare metal or cpanel/whm?

[jeffschips]

Hello. I hope everyone is healthy and safe.

In the process of researching issues with my install I came across a long delay in reverse dns when running this command:

for i in {a..m}; do echo -n "$i.root-servers.net: "; dig -4 "$i".root-servers.net @"$i".root-servers.net +short;done
a.root-servers.net: 198.41.0.4
b.root-servers.net: 199.9.14.201
c.root-servers.net: 192.33.4.12
d.root-servers.net: 199.7.91.13
e.root-servers.net: 192.203.230.10
f.root-servers.net: 192.5.5.241
g.root-servers.net: 192.112.36.4
h.root-servers.net: 198.97.190.53
i.root-servers.net:
; <<>> DiG 9.11.4-P2-RedHat-9.11.4-26.P2.el7_9.13 <<>> -4 i.root-servers.net @i.root-servers.net +short
;; global options: +cmd
;; connection timed out; no servers could be reached
j.root-servers.net: 192.58.128.30
k.root-servers.net:
; <<>> DiG 9.11.4-P2-RedHat-9.11.4-26.P2.el7_9.13 <<>> -4 k.root-servers.net @k.root-servers.net +short
;; global options: +cmd
;; connection timed out; no servers could be reached
l.root-servers.net: 199.7.83.42
m.root-servers.net: 202.12.27.3

My bare metal provider made suggestions like "changing the DNS resolve mode to TTL Cached" although I can't find such a setting in either cpanel/WHM or bare metal settings.

cat resolv.conf
# Generated by NetworkManager
nameserver 208.67.220.220
nameserver 8.8.8.8
nameserver 1.1.1.1
nameserver 8.8.4.4


Clues?

 

[jeffschips]

SOLVED:
somehow csf was blocking two ip addresses. I whitelisted them and now everything runs smoothly.

 

[cPRex]

I'm glad to hear you found the cause!