- Currently using a native vlan other then 1 in our general deployments. Testing the 6509 (sup2-t) running 15.1 (sy7) connecting to a 3850 switch. Want to know whether its possible to use a native vlan other then 1. so the downstream switch ( 3850 ) picks this up during the PnP bootup,. Have been doing packet captures with the team from a new out of box switch, to see what the initial setup traffic looks like, e.g. dhcp requests etc.
So far, consistently, 3 or 4th packet is a dhcp request, to 0.0.0.0, with no vlan id tag in frame.
This leads to believe if they connected this switch to the upstream switch, and configured the upstream switch port trunk native vlan to be the network management VLAN ID, which has a usable L3 address/svi and can route to our DHCP platform (which has usable pool configured), it should be able to obtain an IP address.the pool is also configured with the required option to direct to APIC EM, which is reachable from this vlan. e just require the ability to act as a "host" at first, and pass untagged packets to do required DHCP interactions and find APIC EM. Understand that in long term we might want to use the PNP vlan commands to have the switch configure a management vlan other than vlan1, and therefore match our normal sw mananagement vlan ids, etc.
pnp startup-vlan xxx command is the recommended way to solve this problem.
The blog posts have details on how this works.
got an an ether channel example in this blog too Network Automation with Plug and Play (PnP) – Part 5
You would need to check that your 6k software supports "pnp startup-vlan xx"
You need to take management vlan, native vlan, ether channel, trunks into consideration.
There is also a way to do this without "pnp startup vlan", but you need to create the management vlan on the switch (and depending on the switch, you will need an EEM script to do this).
Also, there are some issues with older versions of 3850 code and NV1 (see PnP release notes for details).