Port 9340 GRIBI
Port 9340 is the IANA-assigned gribi port for gRPC Routing Information Base Interface (TCP).
What is port 9340 used for?
Port 9340 is assigned to gribi and uses TCP. The IANA registry describes the service as “gRPC Routing Information Base Interface”. It sits in the registered range, the block used by databases, application servers and developer tooling. Port conflicts here are common when several local services start at once.
Ports are the transport-layer address a service listens on. A client that wants to reach gribi connects to port 9340. 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 9340 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.
Browse all Networking and proxies ports
Source: IANA Service Name and Transport Protocol Port Number Registry. Registered assignee: [Google_Networking].
Check and block port 9340
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 = :9340'Check on Windows
Get-NetTCPConnection -LocalPort 9340 -State Listen -ErrorAction SilentlyContinueBlock with UFW
sudo ufw deny 9340/tcpBlock with iptables
sudo iptables -A INPUT -p tcp --dport 9340 -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 9340 safe to expose?
This port is not on our curated list of services with a widely exploited profile. Exposure is only safe when the listening service is intended, patched and protected by a firewall. Keep the listening service patched and remove it if unused. A default-deny firewall policy with explicit allow rules is still the safest baseline.
Where port 9340 is usually used
Most traffic on port 9340 falls into these scenarios. The demo below is a safe way to confirm the listener before you change anything.
- Routers, switches and proxies exchanging routing or session information.
- Clients sending traffic through a forward or reverse proxy on port 9340.
- Troubleshooting path selection, NAT or proxy rules during an outage.
Probe the network service
Check reachability from a host on the same path before you inspect device configuration.
nc -vz 127.0.0.1 9340Common problems with port 9340
Connection refused or timed out
Refused usually means the host is reachable but nothing is listening on port 9340. 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 = :9340' or sudo lsof -i :9340. 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 9340 at a glance
| Port number | 9340 |
|---|---|
| Service name | gribi |
| Transport protocol | TCP |
| Category | Networking and proxies |
| Range | Registered port (1024–10000) |
| Risk level | Standard/Low |
| Registered assignee | [Google_Networking] |
| Registry description | gRPC Routing Information Base Interface |
| Source | IANA Service Name and Transport Protocol Port Number Registry |
Frequently asked questions
What is port 9340 used for?
Port 9340 (GRIBI) uses TCP. gRPC Routing Information Base Interface.
How do I check if port 9340 is open?
On Linux run `sudo ss -tlpn 'sport = :9340'`. On Windows run `Get-NetTCPConnection -LocalPort 9340 -State Listen -ErrorAction SilentlyContinue` in PowerShell. If the port is open, the output shows a process listening on port 9340; empty output usually means nothing is bound to it.
How do I block port 9340?
With UFW run `sudo ufw deny 9340/tcp`. With iptables run `sudo iptables -A INPUT -p tcp --dport 9340 -j DROP`. Persist the iptables rules with your distribution's netfilter-persistent or iptables-save tooling so they survive a reboot.
Is port 9340 safe to expose?
This port is not on our curated list of services with a widely exploited profile. Exposure is only safe when the listening service is intended, patched and protected by a firewall. Nevertheless, keep the listening service patched and remove it if unused. A default-deny firewall policy with explicit allow rules is still the safest baseline.
Related ports
- Port 9339 · gnmi-gnoigRPC Network Mgmt/Operations Interface
- Port 9380 · boxpBrivs! Open Extensible Protocol
- Port 6699 · babel-dtlsBabel Routing Protocol over DTLS
- Port 9889 · gt-proxyPort for Cable network related data proxy or repeater
- Port 5196 · ampl-tableproxyThe protocol is used by two programs that exchange "table" data used…
- Port 13217 · rs-piasR&S Proxy Installation Assistant Service
Primary data: IANA Service Name and Transport Protocol Port Number Registry.
Last reviewed 2026-10-30 · Methodology · About · Privacy