topic RE: EXOS: OSPF "passive-interface default" needed in ExtremeSwitching (EXOS/Switch Engine)

EXOS: OSPF "passive-interface default" needed

M_Nees — Mon, 17 Jul 2017 20:12:00 GMT

Currently i configure OSPF on X870 Switches (recent EXOS 22.2.x).

I am looking for a command for setting all vlan to "passive default" like i do it on EOS or Cisco.

Currently i do manually vlan for vlan only.

configure ospf add vlan VLAN-0111 area 172.16.1.0 passive
configure ospf add vlan VLAN-0113 area 172.16.1.0 passive
configure ospf add vlan VLAN-4001 area 172.16.1.0
Is there no default passive statement ?

Regards

RE: EXOS: OSPF "passive-interface default" needed

BrandonC — Mon, 17 Jul 2017 20:14:00 GMT

Hi Matthias,

No, currently there is not an option to configure EXOS in this way. All VLANs added to OSPF are added as active interfaces unless you specify 'passive' in the command.

RE: EXOS: OSPF "passive-interface default" needed

OscarK — Tue, 18 Jul 2017 11:37:00 GMT

Instead of adding every vlan as passive you could just enable ospf on one vlan and then do export direct to export all direct connected vlans into ospf.

RE: EXOS: OSPF "passive-interface default" needed

M_Nees — Tue, 18 Jul 2017 11:37:00 GMT

sounds interessting - but some explanation or example needed ...

RE: EXOS: OSPF "passive-interface default" needed

OscarK — Tue, 18 Jul 2017 11:37:00 GMT

Hello Matthias,

it is very simple, add the vlan where you have ospf neighbors as normal to ospf.
To advertise all your IP vlans into ospf:

enable ospf export direct cost 10 type ase-type-1 (or type 2).

This will advertise all your direct connected subnets (all your routed vlans) to be advertised by OSPF as external ase-type-1 or 2 routes.

RE: EXOS: OSPF "passive-interface default" needed

M_Nees — Tue, 18 Jul 2017 11:37:00 GMT

OK, thanks that explain it ...
Nice mechanism to achieve the goal.

A big disadvantage for me is that in routing table all directed routes a marked as external. That makes routing table unclear / confusing. Normally i do not want this.
So i my projects i avoid this (if i can) ...

So having "passive-interface default" is a needed / missed Feature in current EXOS.

RE: EXOS: OSPF "passive-interface default" needed

Erik_Auerswald — Tue, 18 Jul 2017 11:37:00 GMT

Oscar suggests using redistribution of connected interfaces instead of adding the interface as passive to OSPF. This adds one type 5 LSA for every connected interface to the LSDB of every normal area.

RE: EXOS: OSPF "passive-interface default" needed

Erik_Auerswald — Tue, 18 Jul 2017 12:40:00 GMT

Hello Matthias,

normally, every VLAN I add to OSPF is either passive or of link-type point-to-point. Thus I always specify one or the other keyword(s) and never use the default broadcast network type. This is just one command as opposed to e.g. the S-Series that requires two (one to add the interface, another one to make it passive or specify the network type).

Thanks,
Erik

RE: EXOS: OSPF "passive-interface default" needed

M_Nees — Tue, 18 Jul 2017 12:40:00 GMT

Hi Erik,
i got your idea. Defining point-to-point links avoid the DR and BDR Election etc. So network admin should define the two states - passive = clients networks or point-2-point = OSPF Links to other routers!

Anyway if i am able to define default-interface passive will help to avoid mistakes and increase security level!

But thanks a lot sharing this idea!

Regards,
Matthias

RE: EXOS: OSPF "passive-interface default" needed

M_Nees — Tue, 18 Jul 2017 12:40:00 GMT

RE: EXOS: OSPF "passive-interface default" needed

OscarK — Tue, 18 Jul 2017 12:57:00 GMT

and dont forget, no need to type it all, adding vlan as passive just is one space and p extra.
con ospf add a 0 p
is enough for command:
configure ospf add area 0.0.0.0 passive