Blocked Port Upstream, Pebble Refuses Support

Hello Admincraft, I have found out that Simple Voicechat does not work on a pebblehost VPS server. I ran multiple tests, even having 3 different people try the same tests and come up with their own solutions, however to no avail, we were not sucessful. Here are our findings will attempting to fix SimpleVoicechat: TCPDump:
user@machine:~# sudo tcpdump -n -i any udp port 25586
tcpdump: data link type LINUX_SLL2
tcpdump: verbose output suppressed, use -v[v]... for full protocol decode
listening on any, link-type LINUX_SLL2 (Linux cooked v2), snapshot length 262144 bytes
0 packets captured
29 packets received by filter
0 packets dropped by kernel
user@machine:~# sudo tcpdump -n -i any udp port 25586
tcpdump: data link type LINUX_SLL2
tcpdump: verbose output suppressed, use -v[v]... for full protocol decode
listening on any, link-type LINUX_SLL2 (Linux cooked v2), snapshot length 262144 bytes
0 packets captured
29 packets received by filter
0 packets dropped by kernel
Nmap:
user@machine:~# nmap -sU -p 25586 198.50.250.196
Starting Nmap 7.94SVN ( https://nmap.org ) at 2025-11-08 12:58 EST
Nmap scan report for ip196.ip-198-50-250.net (198.50.250.196)
Host is up.

PORT STATE SERVICE
25586/udp open|filtered unknown

Nmap done: 1 IP address (1 host up) scanned in 2.10 seconds
user@machine:~# nmap -sU -p 25586 198.50.250.196
Starting Nmap 7.94SVN ( https://nmap.org ) at 2025-11-08 12:58 EST
Nmap scan report for ip196.ip-198-50-250.net (198.50.250.196)
Host is up.

PORT STATE SERVICE
25586/udp open|filtered unknown

Nmap done: 1 IP address (1 host up) scanned in 2.10 seconds
nc:
user@machine:~# nc -vzu 198.50.250.196 25586
Connection to 198.50.250.196 25586 port [udp/*] succeeded!
user@machine:~# nc -vzu 198.50.250.196 25586
Connection to 198.50.250.196 25586 port [udp/*] succeeded!
Simple Voicechat's Port Checker:
Port Checker Checking if the port of voice chat server 198.50.250.196:25586 is open.
Pinging voice chat server '198.50.250.196:25586'
Using ping protocol version 1
Resolved address to '198.50.250.196' and port to '25586'
[1/10] No response
[2/10] No response
[3/10] No response
[4/10] No response
[5/10] No response
[6/10] No response
[7/10] No response
[8/10] No response
[9/10] No response
[10/10] No response
Timed out after 10 attempts
Pinging voice chat server '198.50.250.196:25586'
Using ping protocol version 1
Resolved address to '198.50.250.196' and port to '25586'
[1/10] No response
[2/10] No response
[3/10] No response
[4/10] No response
[5/10] No response
[6/10] No response
[7/10] No response
[8/10] No response
[9/10] No response
[10/10] No response
Timed out after 10 attempts
Ports tried: 19132, 24454, 25586 Environments Attempted: - Paper (Non-docker) - Velocity -> Paper (Docker/Pterodactyl) - Paper (Docker/Pterodactyl) - Folia (Docker/Pterodactyl) - Velocity -> Folia (Docker/Pterodactyl) Software Used: - Elytra (Fork of Wings) - Pyrodactyl (Fork of Pterodactyl)
33 Replies
Lunaiskey
Lunaiskey3w ago
youve opened this port through pyrodactyl right? im assuming you have but just checking and that pebblehost doesnt have some form of subnet for opening and closing ports aswell?
Lup @ Discrealms.net
only on their dedicated servers I have
Snow Kit
Snow Kit3w ago
do you have ufw or any firewall enabled?
Lup @ Discrealms.net
I tried with them enabled and disabled
Snow Kit
Snow Kit3w ago
have you checked if there's a problematic iptables rule?
Lup @ Discrealms.net
I flushed them and allowed all in to test this Otherwise, I don’t use iptables on this server
Snow Kit
Snow Kit3w ago
well, both ufw and docker use iptables as a backend for networking
Lup @ Discrealms.net
Correct I don’t think there would be any issues as there were no rules that were set to deny
Snow Kit
Snow Kit3w ago
if you run the simplevoicechat cli ping tool on the host, are you able to ping it either on 127.0.0.1, the public IP or the internal docker IP for the container?
Lup @ Discrealms.net
Another reason why I would assume it would be a pebble issue is that this was tested on 2 different VPS servers with the same outcome. I have not tried that yet
Snow Kit
Snow Kit3w ago
if you don't know the internal IP for a pterodactyl container, you can use the container's ID in pterodactyl seen here as a hostname
No description
Lup @ Discrealms.net
I will test that soon as possible From what I can see, I can ping svc locally
user@machine:~# ./svc ping 172.18.0.2:25586
Sending pings to 172.18.0.2:25586:
Pinging... (1/10)
Got a response in 2ms after 1 attempt(s)
user@machine:~# ./svc ping 172.18.0.2:25586
Sending pings to 172.18.0.2:25586:
Pinging... (1/10)
Got a response in 2ms after 1 attempt(s)
Cooleg
Cooleg3w ago
wait so the mc is publicly accessible but not the svc?
Snow Kit
Snow Kit3w ago
can you run it locally but ping that port on the public IP?
Lup @ Discrealms.net
user@machine:~# ./svc ping 198.50.250.196:25586
Sending pings to 198.50.250.196:25586:
Pinging... (1/10)
Got a response in 1ms after 1 attempt(s)
user@machine:~# ./svc ping 198.50.250.196:25586
Sending pings to 198.50.250.196:25586:
Pinging... (1/10)
Got a response in 1ms after 1 attempt(s)
I will try this again on my computer On my computer
lupancham@macintosh % ./svc ping 198.50.250.196:25586
Sending pings to 198.50.250.196:25586:
Pinging... (1/10)
Pinging... (2/10)
Pinging... (3/10)
Pinging... (4/10)
Pinging... (5/10)
Pinging... (6/10)
Pinging... (7/10)
Pinging... (8/10)
Pinging... (9/10)
Pinging... (10/10)
Timed out after 10 attempt(s)
lupancham@macintosh % ./svc ping 198.50.250.196:25586
Sending pings to 198.50.250.196:25586:
Pinging... (1/10)
Pinging... (2/10)
Pinging... (3/10)
Pinging... (4/10)
Pinging... (5/10)
Pinging... (6/10)
Pinging... (7/10)
Pinging... (8/10)
Pinging... (9/10)
Pinging... (10/10)
Timed out after 10 attempt(s)
Snow Kit
Snow Kit3w ago
Yeah, as far as I'm concerned that would be an issue with the service provider at that point
Lup @ Discrealms.net
They don't want to believe it :shrug:
Snow Kit
Snow Kit3w ago
and pebblehost doesn't have a firewall for VPSs?
Lup @ Discrealms.net
I did get asked at one point to check the vps firewall, but there isn't a location to configure the firewall
Snow Kit
Snow Kit3w ago
what options does the vps panel have under the network tab? I've never used pebble's VPS stuff
Lup @ Discrealms.net
its similar to some already existing hosts, I'll send a screenshot Or I assume they use that one becuase it could be the only option for whcms
Snow Kit
Snow Kit3w ago
I believe it's virtfusion
Lup @ Discrealms.net
Network doesn't contain firewall options
No description
Snow Kit
Snow Kit3w ago
and you can see the ping tool's traffic with tcpdump when it's on the local machine targetted at the public IP, but not when pinging from a remote machine, correct?
Lup @ Discrealms.net
let me re-run that with svc tool and tcpdump running
user@machine:~# sudo tcpdump -n -i any udp port 25586
tcpdump: data link type LINUX_SLL2
tcpdump: verbose output suppressed, use -v[v]... for full protocol decode
listening on any, link-type LINUX_SLL2 (Linux cooked v2), snapshot length 262144 bytes
17:15:39.404537 pterodactyl0 Out IP 172.18.0.1.34453 > 172.18.0.2.25586: UDP, length 42
17:15:39.404540 vethbac46ae Out IP 172.18.0.1.34453 > 172.18.0.2.25586: UDP, length 42
17:15:39.404752 vethbac46ae P IP 172.18.0.2.25586 > 172.18.0.1.34453: UDP, length 24
17:15:39.404752 pterodactyl0 In IP 172.18.0.2.25586 > 172.18.0.1.34453: UDP, length 24
17:15:40.824539 pterodactyl0 Out IP 172.18.0.1.58621 > 172.18.0.2.25586: UDP, length 42
17:15:40.824542 vethbac46ae Out IP 172.18.0.1.58621 > 172.18.0.2.25586: UDP, length 42
17:15:40.824773 vethbac46ae P IP 172.18.0.2.25586 > 172.18.0.1.58621: UDP, length 24
17:15:40.824773 pterodactyl0 In IP 172.18.0.2.25586 > 172.18.0.1.58621: UDP, length 24
17:15:56.884871 pterodactyl0 Out IP 198.50.250.196.54259 > 172.18.0.2.25586: UDP, length 42
17:15:56.884875 vethbac46ae Out IP 198.50.250.196.54259 > 172.18.0.2.25586: UDP, length 42
17:15:56.885117 vethbac46ae P IP 172.18.0.2.25586 > 198.50.250.196.54259: UDP, length 24
17:15:56.885117 pterodactyl0 In IP 172.18.0.2.25586 > 198.50.250.196.54259: UDP, length 24
12 packets captured
425 packets received by filter
0 packets dropped by kernel
user@machine:~# sudo tcpdump -n -i any udp port 25586
tcpdump: data link type LINUX_SLL2
tcpdump: verbose output suppressed, use -v[v]... for full protocol decode
listening on any, link-type LINUX_SLL2 (Linux cooked v2), snapshot length 262144 bytes
17:15:39.404537 pterodactyl0 Out IP 172.18.0.1.34453 > 172.18.0.2.25586: UDP, length 42
17:15:39.404540 vethbac46ae Out IP 172.18.0.1.34453 > 172.18.0.2.25586: UDP, length 42
17:15:39.404752 vethbac46ae P IP 172.18.0.2.25586 > 172.18.0.1.34453: UDP, length 24
17:15:39.404752 pterodactyl0 In IP 172.18.0.2.25586 > 172.18.0.1.34453: UDP, length 24
17:15:40.824539 pterodactyl0 Out IP 172.18.0.1.58621 > 172.18.0.2.25586: UDP, length 42
17:15:40.824542 vethbac46ae Out IP 172.18.0.1.58621 > 172.18.0.2.25586: UDP, length 42
17:15:40.824773 vethbac46ae P IP 172.18.0.2.25586 > 172.18.0.1.58621: UDP, length 24
17:15:40.824773 pterodactyl0 In IP 172.18.0.2.25586 > 172.18.0.1.58621: UDP, length 24
17:15:56.884871 pterodactyl0 Out IP 198.50.250.196.54259 > 172.18.0.2.25586: UDP, length 42
17:15:56.884875 vethbac46ae Out IP 198.50.250.196.54259 > 172.18.0.2.25586: UDP, length 42
17:15:56.885117 vethbac46ae P IP 172.18.0.2.25586 > 198.50.250.196.54259: UDP, length 24
17:15:56.885117 pterodactyl0 In IP 172.18.0.2.25586 > 198.50.250.196.54259: UDP, length 24
12 packets captured
425 packets received by filter
0 packets dropped by kernel
Snow Kit
Snow Kit3w ago
and you see nothing when pinging from a remote machine?
Lup @ Discrealms.net
Nothing as seen here
Snow Kit
Snow Kit3w ago
yeah, then you'll just have to (politely) argue with support and tell them that udp traffic gets dropped before it hits your VPS you can always try to minimally reproduce it with a udp echo server so they can verify on their side (ie: https://serverfault.com/a/347165) with another VM on the same host
Lup @ Discrealms.net
We have another VPS with them that we used and is now just sitting there until the next billing period. I opened a mc server on it with svc with a firewall to allow the ports. Safe to say, I still have the same issue. Now they are doubting themselves and asked for the login to that VPS since it was recreated on 2 separate instances
Solution
Lup @ Discrealms.net
I won the case
Snow Kit
Snow Kit3w ago
:FubukiPartyBird:

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