no core isoalation 17.3R3

Owned by Jean-luc KRIKER
Last updated: Oct 03, 2020
1 min read


Spine + leaf + lag to customer

  • if spine - leaf link lost >> force traffic customer traffic on the other link of the lag

Spine only: 

  •  spine to spine link lost : both spine force the access with to use the other link in the lag ( = none ) >>> so must use no-core-isolation


https://www.juniper.net/documentation/en_US/junos/information-products/topic-collections/release-notes/17.3/jd0e19289.html#jd0e20452


By default, QFX10000, QFX5100, QFX5110, QFX5200, and QFX5210 switches that act as spine and
leaf devices in an EVPN-VXLAN overlay network implement the core isolation feature. If one of these
QFX switches loses all of its EVPN internal BGP (IBGP) peering sessions, the core isolation feature,
working in conjunction with Link Aggregation Control Protocol (LACP), automatically brings down all
Layer 2 Ethernet Switch Identifier (ESI) link aggregation group (LAG) interfaces on the switch. In some
270
situations, this feature produces an undesired outcome that you can prevent by disabling the feature
with the no-core-isolation configuration statement at the [edit protocols evpn] hierarchy level.