Configuring LAN Gateway on Oracle Linux

Ziti Overlay
1

I am working through the instructions in the video produced by @rcsoleng.

After setting up the remote router, I receive the following error when I run it.

FATAL edge/tunnel/dns.NewDnsServer: dns server failed to start: listen udp 10.0.0.121:53: bind: permission denied

What have I done to attempt to resolve this

Checked that port 53 on UDP is open on the firewall and VCN (checked)

Other tips?

I really feel like I am walking in the dark here..

I found this reference in the Oracle help documentation but are not 100% sure what it all means..

Are there other steps that I need to take?
What else can I do to troubleshoot?

https://docs.oracle.com/en/operating-systems/oracle-linux/8/network/network-ConfiguringtheNameService.html

@TheLumberjack

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@gooseleggs … any thoughts?

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Hmm… I think I found the problem.

dig 10.0.0.121

When I run this command, the server could not be reached. However, I find this confusing as this is the output when I run ifconfig

ens3: flags=4163<UP,BROADCAST,RUNNING,MULTICAST>  mtu 9000
        inet 10.0.0.121  netmask 255.255.255.0  broadcast 10.0.0.255
        inet6 fe80::17ff:fe00:2dc7  prefixlen 64  scopeid 0x20<link>
        ether 02:00:17:00:2d:c7  txqueuelen 1000  (Ethernet)
        RX packets 2703151  bytes 3031719249 (2.8 GiB)
        RX errors 0  dropped 0  overruns 0  frame 0
        TX packets 2941664  bytes 2971859794 (2.7 GiB)
        TX errors 0  dropped 0 overruns 0  carrier 0  collisions 0

My understanding is that you need to use the local private IP address for the server… that is attached to the network nic. Is this correct?

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PS… I just logged into the Oracle Cloud admin panel and confirmed the private IP address is 10.0.0.121

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Did you run the router as sudo? Is something already listening on that IP on port 53? Unfortunately, there's probably a bunch of reasons why that can happen. You need to figure out why the router wasn't permitted to bind on UDP port 53. I don't have any other great tips for you on this one.

1 Like
6

Thanks for your feedback. I tried sudo which generated the same error.

Maybe I am going down the wrong direction, as what I really wan to achieve is to configure a ZTNA. ie. I want to make a LAN connection between my laptop and a remote server that contains my private git repository… so that I can perform a push over a ziti network.

Is this how you normally configure this?

Or… is there another way to setup ZTNA that I could use?

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Actually… I am not sure what I did… but I just realised that I have made some progress… as I am now getting a different error

FATAL edge/tunnel/dns.NewDnsServer: dns server failed to start: listen udp 168.138.10.79:53: bind: cannot assign requested address

Any ideas on what this means / where to investigate?

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OK… I think I understand this message… is 168.138.10.79 is the external IP address… which is not included in the /etc/hosts file

So… I should probably use the local IP address… however… I think the reason for permission denied error is because I did not include the private IP address when I rebuilt the controller PKI.

Does this make sense?

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Working… now… I am not 100% sure what specifically I did… but the key things were

  1. needs to run under sudo
  2. I think both TCP 53 and UDP 53 ports need to be opened
  3. resolver needs to use the local IP address: udp://10.0.0.121:53
  4. router CSR… needs to use same details as controller
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Sounds like you got it working, nice!