topic Re: Sandbox DNS resolution is not working in DevNet Sandbox

Sandbox DNS resolution is not working

karim Abou Hashish — Tue, 27 Aug 2024 07:43:39 GMT

Cannot resolve DNS provided in the Lab 10.10.20.100, check attached screenshot

Re: Sandbox DNS resolution is not working

bigevilbeard — Tue, 27 Aug 2024 09:39:19 GMT

Saw this issue before, i think a quick way to fix is add the finesse hostname to your /etc/hosts file or set your primary DNS to 10.10.20.100 once connected to the VPN.

Hope this helps.

Re: Sandbox DNS resolution is not working

jokearns1 — Tue, 27 Aug 2024 10:44:52 GMT

Hi,

Can you send me the link to your topology page (or devnet username) and I will take a look at your reservation.

Joe

Re: Sandbox DNS resolution is not working

karim Abou Hashish — Tue, 27 Aug 2024 10:53:34 GMT

Thanks for helping, here is my details
Environment name: "Unified Contact Center Express 12.5-20240827T09105090"
Environment URL: https://devnetsandbox.cisco.com/DevNet/environments/g8KL020hpm4J/simplified

Re: Sandbox DNS resolution is not working

jokearns1 — Tue, 27 Aug 2024 14:28:35 GMT

Hi,

I VPN connected to your lab and the Win2022 DNS server is working. I am on a MAC so tested the nslookup equivalent:

dig hq-cucm-pub.abc.inc @10.10.20.100

; <<>> DiG 9.10.6 <<>> hq-cucm-pub.abc.inc @10.10.20.100

;; global options: +cmd

;; Got answer:

;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 2371

;; flags: qr aa rd ra; QUERY: 1, ANSWER: 1, AUTHORITY: 0, ADDITIONAL: 1

;; OPT PSEUDOSECTION:

; EDNS: version: 0, flags:; udp: 4000

;; QUESTION SECTION:

;hq-cucm-pub.abc.inc. IN A

;; ANSWER SECTION:

hq-cucm-pub.abc.inc. 3600 IN A 10.10.20.1

;; Query time: 161 msec

;; SERVER: 10.10.20.100#53(10.10.20.100)

;; WHEN: Tue Aug 27 15:25:28 IST 2024

;; MSG SIZE rcvd: 64

Browsing to https://hq-cucm-pub.abc.inc works fine too. Did you try resolution in the browser?

Joe

Re: Sandbox DNS resolution is not working

karim Abou Hashish — Tue, 27 Aug 2024 21:30:01 GMT

i tried an online checker and couldn't find hq-cucm-pub.abc.inc through the DNS 10.10.20.100 (check below screenshot) .sounds like the DNS is not reachable. i'm located in Egypt

Re: Sandbox DNS resolution is not working

jokearns1 — Tue, 27 Aug 2024 21:43:56 GMT

Just to confirm, you are successfully connected to the lab VPN when you try DNS resolution?

Re: Sandbox DNS resolution is not working

karim Abou Hashish — Wed, 28 Aug 2024 00:00:02 GMT

I tried to connect by VPN, i have paloalto client and it is not reachable (same issue as the DNS) --> check below screenshot
VPN URL: devnetsandbox-usw1-reservation.cisco.com:20290

Re: Sandbox DNS resolution is not working

jokearns1 — Wed, 28 Aug 2024 07:52:25 GMT

Hi Karim,

Yes you need to use the Cisco Secure VPN client (Anyconnect) for this. If you open a browser and goto:
https://devnetsandbox-usw1-reservation.cisco.com:20290
login using the credentials provided in your reservation:
You will now have the option to download and install the secure VPN client

Re: Sandbox DNS resolution is not working

jokearns1 — Wed, 28 Aug 2024 07:53:46 GMT

Instructions also available for this: see screenshoots

Re: Sandbox DNS resolution is not working

karim Abou Hashish — Wed, 28 Aug 2024 08:10:51 GMT

Thanks for your help, i tried to install the VPN client but seems that i need some extra access permissions. Don't understand why that might be needed for a client software.

Re: Sandbox DNS resolution is not working

jokearns1 — Wed, 28 Aug 2024 08:33:31 GMT

Let me look into that. I did not think a Service contract was required in this case. We used to be able to make the client available on our site but that recently changed.

Re: Sandbox DNS resolution is not working

bigevilbeard — Wed, 28 Aug 2024 10:38:37 GMT

@karim Abou Hashish you need a valid service contract with Cisco to get anyconnect. Look for OpenConnect, or OpenVPN.

Hope this helps.

Re: Sandbox DNS resolution is not working

bigevilbeard — Wed, 28 Aug 2024 10:41:58 GMT

@karim Abou Hashish you will not be able to resolve this. Private IP addresses like 10.10.20.100 are designed to be used within a private network. This means they aren't directly accessible from the public internet. DNS for a private IP address, you'll need to use an internal DNS server in this case the one in the devnet sandbox as this server is configured within the private network to map domain names to their corresponding private IP addresses.

Hope this helps.