Port 16379 REDIS CLUSTER BUS
Port 16379 is the community default for Redis cluster bus, using TCP.
What is port 16379 used for?
Port 16379 is widely used by Redis cluster bus (TCP), a community convention rather than an IANA assignment. Redis Cluster bus port, conventionally the client port plus 10000 (community convention). It sits above the registered range, where most numbers are transient client ports. A fixed high port is worth documenting precisely because tooling often assumes the default.
Ports are the transport-layer address a service listens on. A client that wants to reach Redis cluster bus connects to port 16379. If nothing is listening, the connection is refused. That is why a port conflict appears whenever two processes try to bind the same number.
Use the commands below to confirm whether port 16379 is actually in use before you change firewall rules. Blocking the port stops new inbound traffic at the firewall, but it does not stop a local process from listening, and it does not remove the service from the machine.
Because this number is not IANA-assigned, a different application may legitimately use it on a machine you do not control. Always identify the actual listening process before deciding that the port belongs to this technology.
Browse all Caching and in-memory stores ports
This port number is not assigned by IANA. The entry documents a widely adopted community convention.
Check and block port 16379
Copy-ready commands for the protocols assigned to this port. Run the check first, then block only what should not be reachable.
Check on Linux
sudo ss -tlpn 'sport = :16379'Check on Windows
Get-NetTCPConnection -LocalPort 16379 -State Listen -ErrorAction SilentlyContinueBlock with UFW
sudo ufw deny 16379/tcpBlock with iptables
sudo iptables -A INPUT -p tcp --dport 16379 -j DROPThese commands are examples for a typical host. Check the listener before you change firewall rules, and persist iptables rules with iptables-save or netfilter-persistent. On Windows, use Windows Defender Firewall or New-NetFirewallRule for persistent blocks. The iptables rules here cover IPv4; mirror them with ip6tables if IPv6 is enabled.
Is port 16379 safe to expose?
The Redis cluster bus carries cluster state and gossip traffic. It must stay inside the cluster network and never be exposed. Treat this port as sensitive. Restrict it to trusted networks or a VPN, require authentication and logging, and never expose it directly to the public internet without a hardened gateway in front.
Where port 16379 is usually used
Most traffic on port 16379 falls into these scenarios. The demo below is a safe way to confirm the listener before you change anything.
- Session storage, rate limiting and hot-key caching in front of a slower database.
- Several application instances sharing counters or job state on port 16379.
- Local development stacks that run the cache in a container.
Probe the cluster bus
The cluster bus is internal Redis traffic, not the client protocol. Only check it from a cluster node.
nc -vz 127.0.0.1 16379Common problems with port 16379
Connection refused or timed out
Refused usually means the host is reachable but nothing is listening on port 16379. A timeout more often means a firewall drop, a wrong host or a service bound to a different interface.
Port already in use
Find the process holding the port with sudo ss -tlpn 'sport = :16379' or sudo lsof -i :16379. Stop that process or configure it to bind another port; killing it without identifying it can take down a production service.
Firewall rule did not survive a reboot
UFW and Windows Firewall keep rules across restarts. Raw iptables rules do not: save them with iptables-save or the netfilter-persistent package, and re-apply after upgrades that reset the ruleset.
The port is blocked but still reachable
A firewall rule filters inbound traffic; it does not close the listener. Confirm with the check command above and bind the service to 127.0.0.1 when only local clients need it.
Port 16379 at a glance
| Port number | 16379 |
|---|---|
| Service name | Redis cluster bus |
| Transport protocol | TCP |
| Category | Caching and in-memory stores |
| Range | High port (10001–65535) |
| Risk level | High |
| Reference | Community convention (not IANA-assigned) |
| Registry description | Redis Cluster bus port, conventionally the client port plus 10000 (community convention) |
| Source | Community convention |
Frequently asked questions
What is port 16379 used for?
Port 16379 (REDIS CLUSTER BUS) uses TCP. Redis Cluster bus port, conventionally the client port plus 10000 (community convention) (community convention, not an IANA assignment).
How do I check if port 16379 is open?
On Linux run `sudo ss -tlpn 'sport = :16379'`. On Windows run `Get-NetTCPConnection -LocalPort 16379 -State Listen -ErrorAction SilentlyContinue` in PowerShell. If the port is open, the output shows a process listening on port 16379; empty output usually means nothing is bound to it.
How do I block port 16379?
With UFW run `sudo ufw deny 16379/tcp`. With iptables run `sudo iptables -A INPUT -p tcp --dport 16379 -j DROP`. Persist the iptables rules with your distribution's netfilter-persistent or iptables-save tooling so they survive a reboot.
Is port 16379 safe to expose?
The Redis cluster bus carries cluster state and gossip traffic. It must stay inside the cluster network and never be exposed. Nevertheless, treat this port as sensitive. Restrict it to trusted networks or a VPN, require authentication and logging, and never expose it directly to the public internet without a hardened gateway in front.
Related ports
Primary data: IANA Service Name and Transport Protocol Port Number Registry. This number is a community convention, not an IANA assignment.
Last reviewed 2026-10-30 · Methodology · About · Privacy