service_chain_v2_vip_management.md

1. Introduction

In service-chaining v2, contrail-svc-monitor allocates service-instance ip from the same subnet for scaling up. This document explains the issue in the current scheme and solutuion for the same.

2. Problem statement

In service-chaining v2, contrail-svc-monitor allocates service-instance ip from the same subnet for scaling up. If the scaling is not required, ip will be wasted which is an issue in the limited ips.

3. Proposed solution

In service-chaining v2, Instead of allocating the service-instance ip from the same subnet, allocate from the diffrent subnet.

4. Implementation

Contrail-api creates network-ipam "service-chain-flat-ipam" with subnets "0.0.0.0/8" and "::ffff/104". Contrail-svc-monitor allocates ipv4 and ipv6 addresses from service-chain-flat-ipam for service-chaining.

5. Performance and scaling impact

5.1 API and control plane

None

5.2 Forwarding performance

None

6. Upgrade

Existing service-chain v2 still would be in the existing scheme. New service-chain v2 will be created with the new scheme.

7. Deprecations

None

8. Dependencies

9. Debugging

10. Testing

10.1 Unit tests

10.2 Dev tests

10.3 System tests

11. Documentation Impact

12. References