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AlexEv123
Enthusiast
Enthusiast

Docker in ESXI Ubuntu VM

Something strange happens in my Ubuntu VM in ESXI 6.7

Container inside Docker can ping gateway, but can not right to download anything.

Its look as VmWare switch forbid I/O operation except PING for container inside Docker.

Is exist special permission to working Ubuntu/CentOS container inside Ubuntu VM?

Maybe nested virtualization or need VLAN setting for container or something else?

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11 Replies
Lalegre
Virtuoso
Virtuoso

Hey @AlexEv123,

Can you ping 8.8.8.8? If you check on your /etc/resolv.conf do you have that DNS configured?

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AlexEv123
Enthusiast
Enthusiast

I don't understand what happening at all.

In my case working only BusyBox, Ubuntu and Centos not working .

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AlexEv123
Enthusiast
Enthusiast

The similar message I see in Ubuntu when I try to observe repository.

Ping is working to any public  IP.

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nachogonzalez
Commander
Commander

Hey, hope you are doing fine:

For what it seems it is a name resolution configuration issue
You can check how the /etc/resolv.conf file is configured (or check here https://linuxize.com/post/how-to-set-dns-nameservers-on-ubuntu-18-04/)

Another thing to consider is if your network has a proxy, that proxy might be blocking connections. 
This post I wrote about how to configure a proxy in docker will work
https://www.nachogonzalez.com.ar/2020/10/20/como-configurar-un-proxy-en-docker/
(It's in Spanish but google translate will do the trick)

Regarding your question:
Out of the box there is no VMware feature that blocks repositories, more also if ping is working to any public IP.

Let me know if you need assistance

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AlexEv123
Enthusiast
Enthusiast

thank you, nachogonzalez

It's a good news that VmWare don't blocking nested virtualization as default.

This issue still don't fixed and I still don't know how to overcome this issue.

But I'm sure this is not a DNS issue, because if I try nslookup I receive correct answer.

# docker run busybox:1.28 nslookup google.com
Server: 8.8.8.8
Address 1: 8.8.8.8 dns.google
Name: google.com
Address 1: 2a00:1450:4001:800::200e fra16s45-in-x0e.1e100.net
Address 2: 172.217.23.110 fra16s45-in-f14.1e100.net

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mahmoodzeeshan
Contributor
Contributor

I am also having same issue. I have even tried installing fresh ubuntu vm on esxi and installed docker using convenient script. Docker service is active but when I try to pull hello-world container, it fails error 408

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mahmoodzeeshan
Contributor
Contributor

I am also having same issue. I have even tried installing fresh ubuntu vm on esxi and installed docker using convenient script. Docker service is active but when I try to pull hello-world container, it times out

Tags (1)
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nachogonzalez
Commander
Commander

Guys, do you have a proxy in your network?

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Lalegre
Virtuoso
Virtuoso

Hey @AlexEv123,

Could you please run iptables -L from your docker host? I am asking these because maybe you are not allowing HTTPS or any other port needed to download the packages.

 

 

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mahmoodzeeshan
Contributor
Contributor

I was able to fix this issue today. In my case issue was related to MTU limitation on my internet connection. I got DSL PPPoE connection and it turns out ISP got MTU limitation over PPPoE connections. Issue was fixed once I configured 1450 mtu on my internet firewall  

Lalegre
Virtuoso
Virtuoso

@mahmoodzeeshan.

Careful there as you could be fragmenting some packets from some OS that does not support fragmentation and you could see some impact in the network performance.

However, nice that you found the solution.

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