Sluggish Web Browsing

[dhalloran]

Hello All

Any idea what would cause web browsing to seem extremely slow and sluggish?
SL-74-x86_64-2017-09-29-LiveDVDkde.iso is the image I used, so it's KDE Desktop Environment. I have tried both Firefox as well as Opera and both seem quiiiite slow going to a web page for the first time.

I have a fresh install of Scientific Linux on a machine I am testing with Microsoft Windows Active Directory Integration. Have the machine added to the domain, and domain users logging in as well! (which i'm quite happy about) Also have nvidia drivers installed thanks to Elrepo.

The web browser seems suuuper slow "right out of the box" so to speak, even before doing a yum update. A fresh install of Cent OS 7 on the same machine, did not have this issue with the same Desktop Environment of KDE. This machine is within the office of a business I work for. Have gone over my firewall, ruled out any and all tcpip settings. I'm thinking it could possibly be something in the kernel? No other machine on our network is having these issues. I have Ubuntu VMs as well that do not have this issue from my host machine, both in bridged and NAT mode.

Anyone else experiencing this??
Any and all help would be suuuper appreciate.
Thank you!

[dhalloran]

An update

So it seems to be a DNS issue? I have two Windows Server 2012 AD Domain Controllers on the network. Using these as DNS servers on scientific linux machine doing a time host shows as follows:

[root@hal9000 etc]# time host fox.com
fox.com has address 23.43.37.127
fox.com mail is handled by 10 mxa-00195501.gslb.pphosted.com.
fox.com mail is handled by 10 mxb-00195501.gslb.pphosted.com.

real 0m12.357s
user 0m0.003s
sys 0m0.006s

12 seconds to resolve a website??? Anyone have any ideas here?
Any other machine on the same LAN, is not having these issues.
Whether it be Win 7, Ubuntu, or even Cent OS... using the same internal DNS servers
I've replicated the issue on a bare metal install of scientific linux, as well as a virtual guest with virtualbox on my Win 7 host.

As a quick workaround, we can edit resolf.conf and use google DNS.
After that, here is the result of a time host

[root@hal9000 etc]# time host fox.com
fox.com has address 23.43.37.127
fox.com mail is handled by 10 mxb-00195501.gslb.pphosted.com.
fox.com mail is handled by 10 mxa-00195501.gslb.pphosted.com.

real 0m1.284s
user 0m0.005s
sys 0m0.005s

If anyone has any thoughts on the matter I would seriously appreciate anyone's input at this point. Thank you!