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Indirect routes are stuck in VRF

‎05-27-2019 03:05 AM

Hi 

 

I got an issue.

 

Many indirect routes are stuck in my VRF and casue my VRF's routing table have more 800,000 routes. But I've rejected these routes leaking from main table.

 

Can you give me some information how to reject it ?

 

> show route summary  table IRENE_R1_CU.inet.0
Autonomous system number: 64050
Router ID: 10.98.146.43

IRENE_R1_CU.inet.0: 830731 destinations, 856339 routes (11838 active, 818893 holddown, 6 hidden)
Direct: 16 routes, 14 active
Local: 14 routes, 5 active
BGP: 856299 routes, 11811 active
Static: 10 routes, 8 active

 

> show route logical-system CHINA table IRENE_R1_CU.inet.0 protocol bgp

IRENE_R1_CU.inet.0: 830731 destinations, 856339 routes (11838 active, 818893 holddown, 6 hidden)
+ = Active Route, - = Last Active, * = Both

1.0.0.0/24 [BGP/170] 3d 04:09:13, localpref 100
AS path: 13335 I, validation-state: unverified
Indirect
1.0.4.0/22 [BGP/170] 3d 04:08:17, localpref 100
AS path: 4826 38803 56203 I, validation-state: unverified
Indirect
1.0.4.0/24 [BGP/170] 01:23:04, localpref 100, from10.98.146.42
AS path: 4826 38803 56203 I, validation-state: unverified
Indirect
1.0.5.0/24 [BGP/170] 01:23:04, localpref 100, from 10.98.146.42
AS path: 4826 38803 56203 I, validation-state: unverified
Indirect

<Omited>

 

1.0.4.0/22 (1 entry, 1 announced)
State: <Record Pending>
BGP Preference: 170/-101
Next hop type: Indirect, Next hop index: 0
Address: 0xb236e10
Next-hop reference count: 189538
Next hop type: Router, Next hop index: 0
Next hop: 10.98.146.65 via lt-1/2/0.1, selected
Label operation: Push 606450
Label TTL action: prop-ttl
Load balance label: Label 606450: None;
Label element ptr: 0x6e514e40
Label parent element ptr: 0x0
Label element references: 5
Label element child references: 1
Label element lsp id: 0
Session Id: 0x0
Next hop: 10.98.146.69 via lt-2/2/0.1
Label operation: Push 606450
Label TTL action: prop-ttl
Load balance label: Label 606450: None;
Label element ptr: 0x6e514e40
Label parent element ptr: 0x0
Label element references: 5
Label element child references: 1
Label element lsp id: 0
Session Id: 0x0
Protocol next hop: 10.98.146.49
Indirect next hop: 0x25932230 1048600 INH Session ID: 0x60e69
State: <Secondary Delete Int Ext>
Local AS: 64050 Peer AS: 64050
Age: 3d 4:09:31 Metric2: 3
Validation State: unverified
Announcement bits (1): 2-RT
AS path: 4826 38803 56203 I (Originator)
Cluster list: 10.98.144.48 10.98.144.46 10.98.147.44 10.98.146.42 10.98.146.45
Originator ID: 10.98.146.49
Communities: 13000:420
Localpref: 100

7 REPLIES 7
Routing

Re: Indirect routes are stuck in VRF

‎05-27-2019 03:35 AM

holddown (routes that are in the pending state before being declared inactive).

A holddown route was once the active route and is no longer the active route. The route is in the holddown state because a protocol still has interest in the route, meaning that the interest bit is set. A protocol might have its interest bit set on the previously active route because the protocol is still advertising the route. The route will be deleted after all protocols withdraw their advertisement of the route and remove their interest bit. A persistent holddown state often means that the interested protocol is not releasing its interest bit properly. However, if you have configured advertisement of multiple routes (with the add-path or advertise-inactive statement), the holddown bit is most likely set because BGP is advertising the route as an active route. In this case, you can ignore the holddown state because nothing is wrong.

 

As per the given 1.0.4.0/22 route details, it is in secondary state and nexthop is lt-1/2/0.1 interface which means that it is leaked from another route table. Could you share the policy configuration which rejects route leaking?

 

Thanks,
Nellikka
JNCIE x3 (SEC #321; SP #2839; ENT #790)
Please Mark My Solution Accepted if it Helped, Kudos are Appreciated too!!!
Routing

Re: Indirect routes are stuck in VRF

‎05-27-2019 05:30 AM
Hi

As I checked, I have rejected routes of protocol BGP, except with community 64050:410. And only allow direct and static routes.

Thus, I confused why I still got hold down routes from some where.

Is it possible that learning from BGP L3 VPN table or other routers?

I will put my policies later.

Many thanks
Cloud
Routing

Re: Indirect routes are stuck in VRF

‎05-28-2019 11:36 AM

Yes, you may be learning from MP-BGP from another PE. For example 10.98.146.42. Check if you have this route in your inet.3 table. In other words, do you have the ldp router or rsvp lsp to 10.98.146.42? 


Mengzhe Hu
JNCIE x 3 (SP DC ENT)
Routing

Re: Indirect routes are stuck in VRF

‎05-28-2019 07:22 PM

Hi 

 

This is also what I can't understand. My bgp.l3vpn table just have 111727 routes.

But my VRF got the 831022.

 

And I also rejected routes leaking into VRF from main.

 

bgp.l3vpn.0: 111727 destinations, 217440 routes (111691 active, 0 holddown, 36 hidden)
BGP: 217440 routes, 111691 active

 

IRENE_R1_CU.inet.0: 831022 destinations, 856581 routes (11955 active, 819067 holddown, 7 hidden)
Direct: 17 routes, 14 active
Local: 15 routes, 2 active
BGP: 856539 routes, 11931 active
Static: 10 routes, 8 active

 

> show configuration routing-options rib-groups
HKG {
import-rib [ inet.0 IRENE_R1_CU.inet.0 ];
import-policy IRENE-TO-VRF;
}

 

set logical-systems CHINA policy-options policy-statement IRENE-TO-VRF term DIRECT from protocol direct

set logical-systems CHINA policy-options policy-statement IRENE-TO-VRF term DIRECT then accept

set logical-systems CHINA policy-options policy-statement IRENE-TO-VRF term LOCAL from protocol local

set logical-systems CHINA policy-options policy-statement IRENE-TO-VRF term LOCAL then accept

set logical-systems CHINA policy-options policy-statement IRENE-TO-VRF term REJECT-BGP from protocol bgp

set logical-systems CHINA policy-options policy-statement IRENE-TO-VRF term REJECT-BGP then reject

set logical-systems CHINA policy-options policy-statement IRENE-TO-VRF term STATIC-ROUTES from protocol static

set logical-systems CHINA policy-options policy-statement IRENE-TO-VRF term STATIC-ROUTES from community 64050:410

set logical-systems CHINA policy-options policy-statement IRENE-TO-VRF term STATIC-ROUTES then local-preference 120

set logical-systems CHINA policy-options policy-statement IRENE-TO-VRF term STATIC-ROUTES then accept

set logical-systems CHINA policy-options policy-statement IRENE-TO-VRF term others then reject

Routing

Re: Indirect routes are stuck in VRF

‎05-29-2019 12:21 PM

Hi,

 

I assume those routes are not learned from CE, right?

 

What I noticed is that some of the routes are pointing to Next Hop of an logical-tunnel (lt-x/x/x). By any chance do you have a lt tunnel between your inet.0 and vrf.inet.0 ?

 

Some times, some customers choose to use a physical loopback or lt between two instances and run protocol to share routes. This is similar to use RIB-GROUP, but you don't want to use both at the same time

 

Regards,

Mengzhe  


Mengzhe Hu
JNCIE x 3 (SP DC ENT)
Routing

Re: Indirect routes are stuck in VRF

‎06-04-2019 07:10 PM

Hi,

 

The interface lt is our logical tunnel between main and logical-system. 

 

And I've used import policy to reject routes learnning from others. But I still got around 80k indirect routes there.

So, it confuses deeply me much.

 

Best regards,

Cloud

Routing

Re: Indirect routes are stuck in VRF

‎06-18-2019 05:49 AM

Hi,

 

How is CPU utilisation? because this may cause the routes draining to be very slow, causingthe routes to get stuck in holddown state. 

Can you post the output of the following commands: 

* show system process extensive

* show krt queue

 

Thanks,

Issam