VNets ID length limited to 8 characters. Why?

[MathieuMD]

Why VNets ID are limited to 8 characters?

ID

An up to 8 character ID to identify a VNet​

Linux interfaces could have up to 15 characters, according to Linux network interface names have a length limit, and Netplan.

 

[nico1875p]

This is not a Linux interface name limitation by itself. The VNet ID is used as a base identifier from which Proxmox automatically generates multiple internal objects (bridge names, veth/tap interfaces, VLAN/VXLAN devices, firewall rules, SDN objects, etc.).
Proxmox needs to append prefixes and suffixes to that ID, so keeping it short avoids exceeding system limits and prevents name collisions.

Limiting the VNet ID to 8 characters is therefore a design choice for consistency and safety across the SDN stack, not a limitation of Linux interface names. Only the Proxmox developers can confirm the exact rationale, but from a technical point of view this makes sense.

 

[shanreich]

This is not a Linux interface name limitation by itself. The VNet ID is used as a base identifier from which Proxmox automatically generates multiple internal objects (bridge names, veth/tap interfaces, VLAN/VXLAN devices, firewall rules, SDN objects, etc.).
Proxmox needs to append prefixes and suffixes to that ID, so keeping it short avoids exceeding system limits and prevents name collisions.

Limiting the VNet ID to 8 characters is therefore a design choice for consistency and safety across the SDN stack, not a limitation of Linux interface names. Only the Proxmox developers can confirm the exact rationale, but from a technical point of view this makes sense.

That's pretty much it, i.e. VLAN devices (ethX.1234) take 5 additional characters for instance. 8 was chosen so there's still some wiggle room for autogenerated names for network devices.

 

[nico1875p]

That's pretty much it, i.e. VLAN devices (ethX.1234) take 5 additional characters for instance. 8 was chosen so there's still some wiggle room for autogenerated names for network devices.

Thanks for confirming. That explains the 8-character limit clearly.

 

[MathieuMD]

Thanks for the explanations!