Well-known · Linux/Unix

892 NFS mountd

TCP Yes
UDP Yes
SCTP
DCCP

What it is

NFSv3 mount daemon.

When / why

NFS mounts; pin and firewall the port.

Protocol status detail

TransportStatusMeaning
TCP Yes Assigned by IANA and standardized, specified, or widely used on this port.
UDP Yes Assigned by IANA and standardized, specified, or widely used on this port.
SCTP Not applicable for this transport.
DCCP Not applicable for this transport.

Port range

Well-known (0–1023). System port for a core service. On Unix-like systems, binding it requires superuser privileges.

Browse all ports →

Firewall rules for port 892

Copy-ready inbound rules for the active transports. Replace every <source> placeholder with the specific host, subnet, or CIDR that should reach this port.

ufw

sudo ufw allow proto tcp from <source> to any port 892

Allow TCP 892 (NFS mountd). Replace <source> with the network/host that should reach it.

sudo ufw allow proto udp from <source> to any port 892

Allow UDP 892 (NFS mountd). Replace <source> with the network/host that should reach it.

firewalld

sudo firewall-cmd --permanent --add-rich-rule='rule family="ipv4" source address="<source>" port port="892" protocol="tcp" accept'

Allow TCP 892 (NFS mountd) from <source>. Run 'firewall-cmd --reload' afterwards.

sudo firewall-cmd --permanent --add-rich-rule='rule family="ipv4" source address="<source>" port port="892" protocol="udp" accept'

Allow UDP 892 (NFS mountd) from <source>. Run 'firewall-cmd --reload' afterwards.

nftables

nft add rule inet filter input ip saddr <source> tcp dport 892 accept

Allow TCP 892 (NFS mountd). Assumes table 'inet filter' with an 'input' chain.

nft add rule inet filter input ip saddr <source> udp dport 892 accept

Allow UDP 892 (NFS mountd). Assumes table 'inet filter' with an 'input' chain.

iptables

sudo iptables -A INPUT -p tcp -s <source> --dport 892 -j ACCEPT

Allow TCP 892 (NFS mountd). Persist with iptables-save/netfilter-persistent.

sudo iptables -A INPUT -p udp -s <source> --dport 892 -j ACCEPT

Allow UDP 892 (NFS mountd). Persist with iptables-save/netfilter-persistent.

Azure NSG

az network nsg rule create -g <resource-group> --nsg-name <nsg> -n Allow-nfsmountd-892 --priority 1000 --access Allow --direction Inbound --protocol "*" --source-address-prefixes <source> --destination-port-ranges 892

Inbound rule for 892 (NFS mountd). Set <source> to a CIDR; lower priority number = higher precedence.

AWS Security Group

aws ec2 authorize-security-group-ingress --group-id <sg-id> --ip-permissions IpProtocol=tcp,FromPort=892,ToPort=892,IpRanges="[{CidrIp=<source-cidr>}]"

Inbound TCP 892 (NFS mountd). Replace <source-cidr> (e.g. 10.0.0.0/16).

aws ec2 authorize-security-group-ingress --group-id <sg-id> --ip-permissions IpProtocol=udp,FromPort=892,ToPort=892,IpRanges="[{CidrIp=<source-cidr>}]"

Inbound UDP 892 (NFS mountd). Replace <source-cidr> (e.g. 10.0.0.0/16).

GCP firewall

gcloud compute firewall-rules create allow-nfsmountd-892 --direction=INGRESS --action=ALLOW --rules=tcp:892,udp:892 --source-ranges=<source-cidr> --network=<network>

Ingress rule for 892 (NFS mountd). Scope with --source-ranges and optionally --target-tags.

Windows netsh

netsh advfirewall firewall add rule name="Allow NFS mountd 892/TCP" dir=in action=allow protocol=TCP localport=892 remoteip=<source>

Inbound TCP 892 (NFS mountd). Set remoteip to a host/subnet; 'any' is discouraged.

netsh advfirewall firewall add rule name="Allow NFS mountd 892/UDP" dir=in action=allow protocol=UDP localport=892 remoteip=<source>

Inbound UDP 892 (NFS mountd). Set remoteip to a host/subnet; 'any' is discouraged.

Windows PowerShell

New-NetFirewallRule -DisplayName "Allow NFS mountd 892/TCP" -Direction Inbound -Action Allow -Protocol TCP -LocalPort 892 -RemoteAddress <source>

Inbound TCP 892 (NFS mountd). Replace <source> with a host or subnet.

New-NetFirewallRule -DisplayName "Allow NFS mountd 892/UDP" -Direction Inbound -Action Allow -Protocol UDP -LocalPort 892 -RemoteAddress <source>

Inbound UDP 892 (NFS mountd). Replace <source> with a host or subnet.

Rules are generated only for transports marked active for this port. They default to an inbound allow with an explicit source placeholder — never any. Review direction, scope, and rule precedence before applying in production.