MFA authentication slow Issue

 

Here's how I found it. I analysed the withduo.cap again and found a key and only network action of the test server when it's lagging was to DNS query for its own hosename but could not get the answer from its DNS server:

 

 

 

So, I wonder whether it is resolving its own hostname(gghjjyy) to ip address that makes it waits for 10s.

 

Here's the hostname resolving setting:

[dddd@gghjjyy~]$ cat /etc/nsswitch.conf
#
# /etc/nsswitch.conf
#
......
hosts:      files dns myhostname

......

 

But /etc/hosts did not contained the record: 158.87.1.16    gghjjyy:

[dddd@gghjjyy ~]$ sudo cat /etc/hosts
[sudo] password for zhangyu:
127.0.0.1   localhost localhost.localdomain localhost4 localhost4.localdomain4
::1         localhost localhost.localdomain localhost6 localhost6.localdomain6
 

So the previous host resolving behavior was waiting until hosts file fails, DNS query fails and then using myhostname.

 

I added 158.87.1.16    gghjjyy to /etc/hosts and then the 2FA login only takes 2-3 seconds.