Registered · Windows

1434 MSSQL Monitor (SQL Browser)

TCP Yes
UDP
SCTP
DCCP

What it is

SQL Server Resolution / Browser service that returns instance ports.

When / why

Named-instance discovery on UDP/1434. Disable if you pin static ports.

Protocol status detail

TransportStatusMeaning
TCP Yes Assigned by IANA and standardized, specified, or widely used on this port.
UDP Not applicable for this transport.
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 1434

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 1434

Allow TCP 1434 (MSSQL Monitor (SQL Browser)). 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="1434" protocol="tcp" accept'

Allow TCP 1434 (MSSQL Monitor (SQL Browser)) from <source>. Run 'firewall-cmd --reload' afterwards.

nftables

nft add rule inet filter input ip saddr <source> tcp dport 1434 accept

Allow TCP 1434 (MSSQL Monitor (SQL Browser)). Assumes table 'inet filter' with an 'input' chain.

iptables

sudo iptables -A INPUT -p tcp -s <source> --dport 1434 -j ACCEPT

Allow TCP 1434 (MSSQL Monitor (SQL Browser)). Persist with iptables-save/netfilter-persistent.

Azure NSG

az network nsg rule create -g <resource-group> --nsg-name <nsg> -n Allow-mssqlmonitorsqlbrowser-1434 --priority 1000 --access Allow --direction Inbound --protocol TCP --source-address-prefixes <source> --destination-port-ranges 1434

Inbound rule for 1434 (MSSQL Monitor (SQL Browser)). 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=1434,ToPort=1434,IpRanges="[{CidrIp=<source-cidr>}]"

Inbound TCP 1434 (MSSQL Monitor (SQL Browser)). Replace <source-cidr> (e.g. 10.0.0.0/16).

GCP firewall

gcloud compute firewall-rules create allow-mssqlmonitorsqlbrowser-1434 --direction=INGRESS --action=ALLOW --rules=tcp:1434 --source-ranges=<source-cidr> --network=<network>

Ingress rule for 1434 (MSSQL Monitor (SQL Browser)). Scope with --source-ranges and optionally --target-tags.

Windows netsh

netsh advfirewall firewall add rule name="Allow MSSQL Monitor (SQL Browser) 1434/TCP" dir=in action=allow protocol=TCP localport=1434 remoteip=<source>

Inbound TCP 1434 (MSSQL Monitor (SQL Browser)). Set remoteip to a host/subnet; 'any' is discouraged.

Windows PowerShell

New-NetFirewallRule -DisplayName "Allow MSSQL Monitor (SQL Browser) 1434/TCP" -Direction Inbound -Action Allow -Protocol TCP -LocalPort 1434 -RemoteAddress <source>

Inbound TCP 1434 (MSSQL Monitor (SQL Browser)). 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.