VLAN Configuration Generator for Cisco, MikroTik and Datacom

VLAN configuration generator

Choose the platform and intended port behavior instead of generating a generic VLAN fragment.

VLAN ID

VLAN name Used by the Cisco profile. Other platforms may not use this value in the generated snippet.

Platform

Configuration type

Cisco interface

RouterOS bridge VLAN filtering

The generated access profile configures PVID, ingress filtering and the bridge VLAN table. Review management access before enabling vlan-filtering to avoid locking yourself out.

Bridge

Trunk / tagged interface

Access / untagged interface Used when the selected configuration type is Access port.

Legacy Datacom profile

This profile generates only interface syntax verified in Datacom legacy documentation. It does not guess a VLAN-creation command for unsupported models or software families.

Datacom interface

802.1Q

A VLAN ID alone is not a complete port configuration

A usable Layer 2 VLAN design also defines where frames enter untagged, where they remain tagged and which VLANs are permitted on trunks. The exact CLI depends on the operating system and hardware family.

CISCO

Access and trunk are explicit interface modes

On common Cisco IOS/IOS XE switching platforms, an access port is placed in a single access VLAN with switchport mode access and switchport access vlan. A trunk uses switchport mode trunk and can restrict which VLANs are carried with switchport trunk allowed vlan.

MIKROTIK

RouterOS uses the bridge VLAN table and PVID together

In RouterOS bridge VLAN filtering, PVID classifies untagged ingress traffic on access ports, while the bridge VLAN table controls tagged and untagged membership. Ingress filtering and frame-type restrictions help prevent traffic from entering through ports where a VLAN is not expected.

DATACOM

Legacy Datacom syntax must not be generalized to DmOS

Datacom has multiple product and software generations. The legacy profile shown here is based on documented switchport commands from older equipment and must not be assumed to represent current DmOS syntax.

CHANGE SAFETY

VLAN changes can remove your own management path

Before enabling filtering, changing a native/PVID setting or removing VLAN membership, confirm how the device itself is reached. Console or out-of-band access is preferable for disruptive VLAN migrations.

Frequently asked questions

What is the difference between an access port and a trunk?+

An access port normally connects an endpoint to one VLAN and sends that traffic untagged. A trunk normally connects VLAN-aware devices and carries one or more VLANs with tags.

Why does the Cisco trunk use "allowed vlan add"?+

Using add preserves the existing allowed VLAN list and adds the requested VLAN. Replacing the entire list unintentionally could remove other VLANs from an operational trunk.

Why does MikroTik need more than a bridge VLAN entry?+

Because access behavior also depends on the bridge-port PVID and filtering rules. The bridge VLAN table defines where the VLAN is tagged or untagged, while PVID classifies untagged ingress traffic.

Can enabling vlan-filtering disconnect a MikroTik?+

Yes. If management VLAN membership and the CPU/bridge path are not configured correctly, enabling bridge VLAN filtering can remove management connectivity.

Why does the Datacom option not create the VLAN?+

The available official legacy documentation confirms interface access/trunk syntax, but Datacom has multiple software families. The tool avoids inventing a VLAN-creation command that may be wrong for the target model.

Does this generator support native VLANs or hybrid ports?+

Not in this baseline version. Those cases add platform-specific behavior and should be configured only when the intended tagging model is clear.

Is VLAN 1 always safe to use?+

No. VLAN 1 often has default or platform-specific behavior. Production designs commonly restrict or avoid it for user and management traffic depending on the platform and architecture.