diff options
| author | Anuradha Karuppiah <anuradhak@cumulusnetworks.com> | 2020-05-08 16:35:09 -0700 |
|---|---|---|
| committer | Anuradha Karuppiah <anuradhak@cumulusnetworks.com> | 2020-10-26 10:26:21 -0700 |
| commit | 74e2bd891d85d68250ce368cb538fb5404867238 (patch) | |
| tree | c8c58d5103b2227432f4a49d412fdef730178612 /lib/stream.h | |
| parent | 070a7cd8bd71b8fde4d8d0b2b6d4e24dd5a4bb7b (diff) | |
bgpd: support for DF election in EVPN-MH
DF (Designated forwarder) election is used for picking a single
BUM-traffic forwarded per-ES. RFC7432 specifies a mechanism called
service carving for DF election. However that mechanism has many
disadvantages -
1. LBs poorly.
2. Doesn't allow for a controlled failover needed in upgrade
scenarios.
3. Not easy to hw accelerate.
To fix the poor performance of service carving alternate DF mechanisms
have been proposed via the following drafts -
draft-ietf-bess-evpn-df-election-framework
draft-ietf-bess-evpn-pref-df
This commit adds support for the pref-df election mechanism which
is used as the default. Other mechanisms including service-carving
may be added later.
In this mechanism one switch on an ES is elected as DF based on the
preference value; higher preference wins with IP address acting
as the tie-breaker (lower-IP wins if pref value is the same).
Sample output
=============
>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
torm-11# sh bgp l2vpn evpn es 03:00:00:00:00:01:11:00:00:01
ESI: 03:00:00:00:00:01:11:00:00:01
Type: LR
RD: 27.0.0.15:6
Originator-IP: 27.0.0.15
Local ES DF preference: 100
VNI Count: 10
Remote VNI Count: 10
Inconsistent VNI VTEP Count: 0
Inconsistencies: -
VTEPs:
27.0.0.16 flags: EA df_alg: preference df_pref: 32767
>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
torm-11# sh bgp l2vpn evpn route esi 03:00:00:00:00:01:11:00:00:01
*> [4]:[03:00:00:00:00:01:11:00:00:01]:[32]:[27.0.0.15]
27.0.0.15 32768 i
ET:8 ES-Import-Rt:00:00:00:00:01:11 DF: (alg: 2, pref: 100)
>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
Signed-off-by: Anuradha Karuppiah <anuradhak@cumulusnetworks.com>
Diffstat (limited to 'lib/stream.h')
| -rw-r--r-- | lib/stream.h | 10 |
1 files changed, 10 insertions, 0 deletions
diff --git a/lib/stream.h b/lib/stream.h index 23f85d809b..4f75f121ca 100644 --- a/lib/stream.h +++ b/lib/stream.h @@ -386,6 +386,16 @@ static inline const uint8_t *ptr_get_be32(const uint8_t *ptr, uint32_t *out) return ptr + 4; } +static inline uint8_t *ptr_get_be16(uint8_t *ptr, uint16_t *out) +{ + uint16_t tmp; + + memcpy(&tmp, ptr, sizeof(tmp)); + *out = ntohs(tmp); + + return ptr + 2; +} + /* * so Normal stream_getX functions assert. Which is anathema * to keeping a daemon up and running when something goes south |