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I installed CentOS 9 on VMWare Workstation 16 Player using an ISO file downloaded from the official website. However, I can't browse the internet from the guest OS.

Setup:

  • Host OS: Windows 10
  • Guest OS: CentOS 9
  • Network Connection: Wi-Fi (corporate network, behind a firewall)
  • VM Network Adapter Mode: NAT (configured in VMware settings)
  • Connectivity Test:
    • ✅ I can ping the host from the guest.
    • ✅ I can ping 8.8.8.8 from the guest.
    • ❌ I cannot browse the internet from the guest.

What I Have Tried:

  1. Verified that the host machine has an active internet connection.
  2. Checked the network configuration using ifconfig inside the guest.
  3. Ensured that the VM network adapter is set to NAT in VMware settings.

Screenshots:

  • VM Network Configuration:
    Network Settings
  • ifconfig Output:
    ifconfig
  • Failed Internet Connection:
    No Internet

Question:

How can I troubleshoot and fix the internet connectivity issue for my CentOS 9 virtual machine?
Is there anything specific related to corporate Wi-Fi networks and VMware NAT that might be blocking the connection?

Any help would be appreciated!

Note that If I switch from Corp Wi-Fi to my own Wi-Fi (smartphone hotspot) and edit /etc/resolv.conf file adding the following line for adding a public DNS server: nameserver 8.8.8.8 it works

cachius
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tail
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2 Answers2

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I have the same problem on a win11 with NAT on vmware fusion on my enterprise network.

In my case, the enterprise firewall blocks the "dns over https" (DoH). When you are using the nat, the DNS serveur in the vm is vmware and vmware forwards the dns requests using DoH.

I don't have figure out how to disable this behavior In the VM, you can manually set the enterprise DNS to bypass the VMWare DNS.

Thibault C
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If you can ping outside IPs but not browse with a web-browser that indicates it's a DNS problem and the VM can't resolve hostnames. Even though NAT or bridge mode allows internet access to ip adresses, the browser must know which one to connect to for google.com. This is DNS's task. Either assign the same name server the host uses to the VM or use DoH.

  • Does browsing work in the Windows host?
  • Compare the output of nslookup example.com on your Windows host and on your VM, from package bind-utils. This should give you the default name server of the company network and it should be identical in both environments. If it is not, add the one from the host PC to /etc/resolv.conf to the VM with a line like nameserver 192.168.254.5. Make sure to use the IP, as the VM might not be able to resolve host names.
    The DNS servers can differ if the Windows host is an AD member and gets it's DNS server configured via GPO, which doesn't apply to the Linux VM, which might get a different DNS server via DHCP or none at all.

nslookup in Windows:

nslookup example.com
Server:  resolver.companynet.local
Address:  192.168.254.5

Non-authoritative answer:
Name:    example.com
Addresses:  96.7.128.175
          23.215.0.138
          ...

nslookup in VM without DNS server:

nslookup example.com
;; communications error to ::1#53: connection refused
;; communications error to 127.0.0.1#53: connection refused
;; no servers could be reached
  • Being able to ping DNS servers is not enough, it could be that DNS name resolution on port 53 is blocked for external name servers in your company network. To check if using external DNS servers is possible, see what nslookup example.com 8.8.8.8 returns (in package bind-utils). Should be similar to
nslookup example.com 8.8.8.8

Server:     8.8.8.8
Address:    8.8.8.8#53


Non-authoritative answer:
Name:   example.com
Address: 96.7.128.198
Name:   example.com
Address: 96.7.128.175
...

  • Check if it works if you add a /etc/hosts entry for a page like 96.7.128.198 example.com. You can use HOSTALIASES to go without root. You would need to set network.dns.offline-localhost to false in about:config

  • Enable DNS over HTTPS in Firefox to use an alternative name resolution method.

cachius
  • 859