Registered · Network

1985 Cisco HSRP

TCP Assigned
UDP Yes
SCTP
DCCP

What it is

Hot Standby Router Protocol gateway redundancy.

When / why

First-hop redundancy between Cisco routers.

Protocol status detail

TransportStatusMeaning
TCP Assigned Assigned by IANA, but not 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

Registered (1024–49151). Assigned by IANA on request; usable without elevated privileges on most systems.

Browse all ports →

Firewall rules for port 1985

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 udp from <source> to any port 1985

Allow UDP 1985 (Cisco HSRP). 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="1985" protocol="udp" accept'

Allow UDP 1985 (Cisco HSRP) from <source>. Run 'firewall-cmd --reload' afterwards.

nftables

nft add rule inet filter input ip saddr <source> udp dport 1985 accept

Allow UDP 1985 (Cisco HSRP). Assumes table 'inet filter' with an 'input' chain.

iptables

sudo iptables -A INPUT -p udp -s <source> --dport 1985 -j ACCEPT

Allow UDP 1985 (Cisco HSRP). Persist with iptables-save/netfilter-persistent.

Azure NSG

az network nsg rule create -g <resource-group> --nsg-name <nsg> -n Allow-ciscohsrp-1985 --priority 1000 --access Allow --direction Inbound --protocol UDP --source-address-prefixes <source> --destination-port-ranges 1985

Inbound rule for 1985 (Cisco HSRP). 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=udp,FromPort=1985,ToPort=1985,IpRanges="[{CidrIp=<source-cidr>}]"

Inbound UDP 1985 (Cisco HSRP). Replace <source-cidr> (e.g. 10.0.0.0/16).

GCP firewall

gcloud compute firewall-rules create allow-ciscohsrp-1985 --direction=INGRESS --action=ALLOW --rules=udp:1985 --source-ranges=<source-cidr> --network=<network>

Ingress rule for 1985 (Cisco HSRP). Scope with --source-ranges and optionally --target-tags.

Windows netsh

netsh advfirewall firewall add rule name="Allow Cisco HSRP 1985/UDP" dir=in action=allow protocol=UDP localport=1985 remoteip=<source>

Inbound UDP 1985 (Cisco HSRP). Set remoteip to a host/subnet; 'any' is discouraged.

Windows PowerShell

New-NetFirewallRule -DisplayName "Allow Cisco HSRP 1985/UDP" -Direction Inbound -Action Allow -Protocol UDP -LocalPort 1985 -RemoteAddress <source>

Inbound UDP 1985 (Cisco HSRP). 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.