OSPF Edge mode on XOS

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Hello all

We have recently bought a couple of E4G-400 switches which have the Advanced Edge license  and MPLS feature pack with XOS 15.2.3.2, as received from Extreme.  We were having some problems getting OSPF working between them (neighbours seemed to get stuck in state ODR) when we came across this statement from the XOS 15.2 Concepts Guide:

===================================================================
  OSPF Edge Mode
OSPF Edge Mode is a subset of OSPF available on platforms with an  advanced Edge license. There are two restrictions on OSPF Edge Mode:
● At most, four Active OSPF VLAN interfaces are permitted. There is no restriction on the number of Passive interfaces.
● The OSPF Priority on VLANs is 0, and is not configurable. This prevents the system from acting as a DR or BDR
===================================================================

The second point seems important.  My understanding is that a DR is required for OSPF routes to be propagated, i.e. it's the DR's job to converge on a network topology.  Without a DR, we can't decide what the network looks like and therefore can't distribute our loopback addresses.

Would it if fair to say that, on some network segment, at least one device with a core license is required for OSPF to work in a reasonable way, i.e. such that a DR exists and loopback /32's are propagated between devices?  If not, what am I missing, given that neither switch in our setup showed any OSPF routes?

Our intention is to create some MPLS L2VPNs (VPWS) with SyncE for cellular backhaul.  It looks like we can get things working with static routes to the /32 loopback addresses (this setup only has 2 switches, so it's easy) but it would be good to know if we're missing something.  That 'something' may be a clue (please apply the cluebat) or an appropriate license.

Regards
Warwick
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Warwick Duncan

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Posted 4 years ago

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PARTHIBAN CHINNAYA, Alum

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Hello ,
By default ospf network type is broadcast .
With network type broadcast DR BDR is needed.
Change the ospf network type to point-to-point. This will fix your problem .
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Warwick Duncan

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Hi

That did the trick, thanks very much.

Regards
Warwick
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M.Nees, Embassador

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I ran into the same issue !

Thanks for your suggestion PARTHIBAN.