This replaces manual checks of the flag with a wrapper macro to convey
the meaning "is evpn enabled on this vrf?"
Signed-off-by: Tuetuopay <tuetuopay@me.com>
Sponsored-by: Scaleway
Rename {bgp,zvrf}_def{ault} to {bgp,zvrf}_evpn where it makes sense,
i.e. when they contain the EVPN instance.
Signed-off-by: Tuetuopay <tuetuopay@me.com>
Sponsored-by: Scaleway
Since the EVPN VRF may not be the default one, compare received
messages' VRF agains the EVPN VRF and not the Default.
Signed-off-by: Tuetuopay <tuetuopay@me.com>
Sponsored-by: Scaleway
This uses the EPVN VRF to store L3VNIs hashes, and looks up L2VNIs in
this VRF as they are stored there.
Signed-off-by: Tuetuopay <tuetuopay@me.com>
Sponsored-by: Scaleway
This sends local VNIs and local MAC addresses to the BGP instance
responsible for EVPN rather than the default one.
Signed-off-by: Tuetuopay <tuetuopay@me.com>
Sponsored-by: Scaleway
If the EVPN VRF is not the default one (i.e. with advertise-all-vni),
this allows showing its information with `show bgp l2evpn evpn ...`
commands. They do not require adding `vrf VRFNAME` since we only
support a single EVPN VRF. The same is true for zebra-specific commands
(e.g. `show evpn ...`).
Configuration commands are not restricted to the default VRF but to
the EVPN one, that is to the one bearing `advertise-all-vni`.
Signed-off-by: Tuetuopay <tuetuopay@me.com>
Sponsored-by: Scaleway
The EVPN VRF is defined by bgpd, and is the one vrf where
`advertise-all-vni` is present.
Signed-off-by: Tuetuopay <tuetuopay@me.com>
Sponsored-by: Scaleway
Duplicate address detection and recovery was relying on the l2-vni backptr
in the neighbor entry which was simply not initialized resulting in
a NULL pointer access in a setup with dup-addressed VMs -
VM1:{IP1,M1} and VM2:{IP1,M2}
Call stack:
(gdb) bt 6
at lib/sigevent.c:249
nbr=nbr@entry=0x559347f901d0, vtep_ip=..., vtep_ip@entry=..., do_dad=do_dad@entry=true,
is_dup_detect=is_dup_detect@entry=0x7ffc7f6be59f, is_local=is_local@entry=true)
at ./lib/ipaddr.h:86
ip=0x7ffc7f6be6f0, ifp=0x559347f901d0, zvni=0x559347f86800) at zebra/zebra_vxlan.c:3152
(More stack frames follow...)
(gdb) p nbr->zvni
$8 = (zebra_vni_t *) 0x0 <<<<<<<<<<<<<<<<<<<<
(gdb)
Signed-off-by: Anuradha Karuppiah <anuradhak@cumulusnetworks.com>
When we get a neighbor entry in zebra we start processing it.
Let's add some additional debugs to the processing so that when
it bails out and we don't use the data, we know the reason.
This should help in debugging the problems from why bgp does
not appear to have data associated with a neighbor entry
in the kernel.
Signed-off-by: Donald Sharp <sharpd@cumulusnetworks.com>
In the case of EVPN symmetric routing, the tenant VRF is associated with
a VNI that is used for routing and commonly referred to as the L3 VNI or
VRF VNI. Corresponding to this VNI is a VLAN and its associated L3 (IP)
interface (SVI). Overlay next hops (i.e., next hops for routes in the
tenant VRF) are reachable over this interface.
https://tools.ietf.org/html/draft-ietf-bess-evpn-prefix-advertisement
section 4.4 provides additional description of the above constructs.
The implementation currently derives this L3 interface for EVPN tenant
routes using special code that looks at route flags. This patch
exchanges the L3 interface between zebra and bgpd as part of the L3-VNI
exchange in order to eliminate some this special code.
Signed-off-by: Vivek Venkatraman <vivek@cumulusnetworks.com>
Reviewed-by: Anuradha Karuppiah <anuradhak@cumulusnetworks.com>
Reviewed-by: Donald Sharp <sharpd@cumulusnetworks.com>
Commit: 6005fe55bc
Introduced a crash with zebra looking up either the
nbr structure or the mac structure. This is because
the zvni used is NULL and we eventually call a hash_lookup
call that would cause a NULL dereference. Partially
revert this commit to original behavior.
Problems found via clang Static Analyzer.
Signed-off-by: Donald Sharp <sharpd@cumulusnetworks.com>
In Asymmetric and symetric routing scenario in EVPN
where each VTEP pair having different set of addresses
for the SVIs.
This knob allows reachability (ping connectivity) of
SVI IPs and resolve ARP resoultion VTEPs across racks.
This knob should not be used when same SVI IPs configured
on VTEPs across racks or when advertise default gateway
is configured.
Ticket:CM-23782
Testing Done:
Bring up EVPN symmetric routing topology with different
SVI IPs on different VTEPs. Enable advertise svi ip
at each VTEP, remote VTEPs installs arp entry for
SVI IPs via EVPN type-2 route exchange.
Signed-off-by: Chirag Shah <chirag@cumulusnetworks.com>
The master thread handler is really part of the zrouter structure.
So let's move it over to that. Eventually zserv.h will only be
used for zapi messages.
Signed-off-by: Donald Sharp <sharpd@cumulusnetworks.com>
In extended-mobility case ({IP1, MAC} binding),
when a MAC moves from local to remote, binding
changes to {IP2, MAC}, local neigh (IP1) marked
as inactive in frr.
The evpn draft recommends to probe the entry once
local binding changes from local to remote.
Once the probe is set for the local neigh entry,
kernel will attempt refresh the entry via sending
unicast address resolution message, if host does not
reply, it will mark FAILED state.
For FAILED entry, kernel triggers delete neigh
request, which result in frr to remove inactive entry.
In absence of probing and aging out entry,
if MAC moves back to local with {IP3, MAC},
frr will mark both IP1 and IP3 as active and sends
type-2 update for both.
The IP1 may not be active host and still frr advertises
the route.
Ticket:CM-22864
Testing Done:
Validate the MAC mobilty in extended mobility scenario,
where local inactive entry gets removed once MAC moves
to remote state.
Once probe is set to the local entry, kernel triggers
reachability of the neigh/arp entry, since MAC moved remote,
ARP request goes to remote VTEP where host is not residing,
thus local neigh entry goes to failed state.
Frr receives neighbor delete faster and removes the entry.
Signed-off-by: Chirag Shah <chirag@cumulusnetworks.com>
Neigh detected duplicate detected during local update,
upon receiving kernel neigh delete, set neigh inactive
flag so BGPd can install remote route entry if present.
Only if freeze action enabled, local duplicate detected
entry will not be present in BGPd thus marking neigh
inactive is safe. BGPd will simply attempt install
remote entry if present.
Ticket:CM-23438
Testing Done:
Validated MAC-IP pair, trigger mobility of between two
VTEPs, upon local freeze perform neigh delete which
triggers BGP to install remote type-2 route into kernel.
Signed-off-by: Chirag Shah <chirag@cumulusnetworks.com>
A MACIP is detected as duplicate and after that
the host continue to move behind different VTEPs results
in local VTEP receiving remote mobility events.
In remote_macip_add, ensure to trigger dad if
MAC is marked as duplicate. In case of freeze
action enabled, is_dup_detect will be set to
avoids installing frozen MAC into kernel.
Ticket:CM-23649
Testing Done:
Configured detection action freeze with detection count
as 7 at DUT and >7 at remote VTEP,
trigger MAC-IP mobility between VTEPs.
once tdetection count reached, MAC detected as duplicate,
post detection move the host to remote. The local VTEP
receives remote macip add and entry is not installed into
kernel with fix.
root@VTEP1:~# net show evpn mac vni 1002 mac aa:aa:aa:aa:aa:aa
MAC: aa:aa:aa:aa:aa:aa
Remote VTEP: 27.0.0.16
Local Seq: 7 Remote Seq: 8
Duplicate, detected at Fri Jan 25 05:03:29 2019
Neighbors:
11.11.11.11 Inactive
Kernel entry still points to LOCAL
root@VTEP1:~# bridge fdb show | grep aa:aa:aa
aa:aa:aa:aa:aa:aa dev hostbond3 vlan 1002 master VxLanA-1
Signed-off-by: Chirag Shah <chirag@cumulusnetworks.com>
When a local neigh is added with a MAC that is remote or absent the
neigh is kept in zebra as local/in-active. But not propagated to bgpd.
Similarly when an inactive neigh is deleted the del-msg is not propagated
to bgpd.
Without this change bgp and zebra would fall out of sync as that
bgp would not know to rerun bestpath and for it to reinstall a
known remote path for the mac-ip in question. To fix this we
now propagate inactive neigh deletes to bgpd.
Ticket: CM-23018
Testing Done:
1. evpn-min
2. manually triggered the out-of-sync state and verified the fix
Signed-off-by: Anuradha Karuppiah <anuradhak@cumulusnetworks.com>
For neigh check duplicate flag as it can be inherited from
duplicate detected MAC (count could be 0).
Ticket:CM-23316
Signed-off-by: Chirag Shah <chirag@cumulusnetworks.com>
Below are cases where EVPN duplicate detection
Freeze and Unfreeze required fixes:
Auto recovery needs to check neighbor's duplicate flag
to take action, as neigh could be marked duplicate
via inherited from MAC where IP detection count could be 0.
MAC duplicate detection needs to set flag to true
if freeze action is configured.
Local MAC add update should not send update to bgp
if MAC is in frozen state.
Remote MAC-IP update should not process neigh update if MAC
is detected as duplicate during remote update.
Ticket:CM-23344
Testing Done:
Trigger duplicate detection via both local and remote update trigger,
Validate clear command and other changes expected behavior.
Auto-recovery takes appropriate action on inherited IPs.
Signed-off-by: Chirag Shah <chirag@cumulusnetworks.com>
Duplicate address detection should operate
at default vrf instance.
For mac and neigh show command, auto recovery and few places
where tanent vrf_id used for zvrf instead use default
vrf instance. Use vxlan_if's or VRF_DEFAULT vrf_id to
fetch zebra's default vrf instance.
Signed-off-by: Chirag Shah <chirag@cumulusnetworks.com>
An EVPN type-2 entry is in freeze state during remote update,
remote VTEP can send typ-2 withdraw update,
upon receiving an entry delete (withdraw), first check
kernel has in local reachable state. Upon
unfreeze use the local entry to advertise to peers.
Fetch is for both MAC and IP, delete can come for
only MAC or MAC-IP combined route.
The specific entry fetch only required request flag to be set,
dump flag is not required.
Testing Done:
Simulate two VTEPs to do M1, IP1 mobility sequence,
freeze MAC during remote MAC update, subsequently send
withdraw type-2 route from origintating VTEP.
This results in read apis to invoke for local reachable entry.
Zebra updates its cache and upon unfreeze originates type-2.
Signed-off-by: Chirag Shah <chirag@cumulusnetworks.com>
the default vrf name was hardset to "Default", whereas the default vrf
name could have been configured in an other manner. Fix this
inconsistency.
Signed-off-by: Philippe Guibert <philippe.guibert@6wind.com>
the l3vni structure is allocated only once, since that structure is only
used for default netns. For that, move the initialisation part is moved
to a proper place, where there is no risk of attempting to initialise it
more than once, even when vrf backend is netns.
Signed-off-by: Philippe Guibert <philippe.guibert@6wind.com>
Clear dup address vni needs to return non-zero value
in case of command is not successful.
Ticket:CM-23122
Testing Done:
run clear command and check upon failure return code is non-zero.
root@TORS1:~# vtysh -c "clear evpn dup-addr vni 1000 ip 45.0.1.26"
% Requested IP's associated MAC 00:01:02:03:04:05 is still in duplicate
% state
root@TORS1:~# echo $?
1
Signed-off-by: Chirag Shah <chirag@cumulusnetworks.com>
Change helps display detailed output for all possible VNI neighbors
without specifying VNI and ip. It helps in troubleshooting as a single
command can be fired to capture detailed info on all VNIs.
Ticket: CM-22832
Signed-off-by: Nitin Soni <nsoni@cumulusnetworks.com>
Reviewed-by: CCR-8034
Change helps display detailed output for all possible VNI MACs without
specifying VNI or mac. It helps in troubleshooting - a single
command can be fired to capture detailed info on all VNIs.
Also fixed and existing json related bug where json object is created by
a parent function and freed in child function.
Ticket: CM-22832
Signed-off-by: Nitin Soni <nsoni@cumulusnetworks.com>
Reviewed-by: CCR-8028
Change helps display detailed output for all possible VNIs without
specifying VNI. It helps in troubleshooting - a single command can
be fired to capture detailed info on all VNIs.
Ticket: CM-22831
Signed-off-by: Nitin Soni <nsoni@cumulusnetworks.com>
Reviewed-by: CCR-8013
Display following Per MAC and Neigh's output:
If duplicate address detection is under process,
display detection start time and detection count.
If duplicate address detection detected an address
as duplicate, display detection time and duplicate
status.
Signed-off-by: Chirag Shah <chirag@cumulusnetworks.com>
When the remote mac is deleted by bgpd we can end up with an auto mac
entry in zebra if there are neighs referring to the mac. The remote sequence
number in the auto mac entry needs to be reset to 0 as the mac entry may
have been removed on all VTEPs (including the originating one).
Now if the MAC comes back on a remote VTEP it may be added with MM=0 which
will NOT be accepted if the remote seq was not reset in the previous step.
Ticket: CM-22707
Signed-off-by: Anuradha Karuppiah <anuradhak@cumulusnetworks.com>
Signed-off-by: Vivek Venkatraman <vivek@cumulusnetworks.com>
This is a fixup to commit -
f32ea5c07 - zebra: act on kernel notifications for remote neighbors
The original commit handled a race condition between kernel and zebra
that would result in an inconsistent state i.e.
kernel has an offload/remote neigh
zebra has a local neigh
The original commit missed setting the neigh to active when zebra
tried to resolve the inconsistency by modifying the local neigh to
remote neigh on hearing back its own kernel update. Fixed here.
Signed-off-by: Anuradha Karuppiah <anuradhak@cumulusnetworks.com>
Signed-off-by: Vivek Venkatraman <vivek@cumulusnetworks.com>
Ticket: CM-22700
When events cross paths between bgp and zebra bgpd could end up with a
dangling local MAC entry. Consider the following sequence of events on
rack-1 -
1. MAC1 has MM sequence number 1 and points to rack-3
2. Now a packet is rxed locally on rack-1 and rack-2 (simultaneously) with
source-mac=MAC1.
3. This would cause rack-1 and rack-2 to set the MM seq to 2 and
simultaneously report the MAC as local.
4. Now let's say on rack-1 zebra's MACIP_ADD is in bgpd's queue. bgpd
accepts rack-3's update and sends a remote MACIP add to zebra with MM=2.
5. zebra updates the MAC entry from local=>remote.
6. bgpd now processes zebra's "stale local" making it the best path.
However zebra no longer has a local MAC entry.
At this point bgpd and zebra are effectively out of sync i.e. bgpd has a
local-MAC which is not present in the kernel or in zebra.
To handle this window zebra should send a local MAC delete to bgpd on
modifying its cache to remote.
Ticket: CM-22687
Reviewed By: CCR-7935
Signed-off-by: Anuradha Karuppiah <anuradhak@cumulusnetworks.com>
The `struct zebra_ns` data structure is being used
for both router information as well as support for
the vrf backend( as appropriate ). This is a confusing
state. Start the movement of `struct zebra_ns` into
2 things `struct zebra_router` and `struct zebra_ns`.
In this new regime `struct zebra_router` is purely
for handling data about the router. It has no knowledge
of the underlying representation of the Data Plane.
`struct zebra_ns` becomes a linux specific bit of code
that allows us to handle the vrf backend and is allowed
to have knowledge about underlying data plane constructs.
When someone implements a *bsd backend the zebra_vrf data
structure will need to be abstracted to take advantage of this
instead of relying on zebra_ns.
Signed-off-by: Donald Sharp <sharpd@cumulusnetworks.com>
The ->hash_cmp and linked list ->cmp functions were sometimes
being used interchangeably and this really is not a good
thing. So let's modify the hash_cmp function pointer to return
a boolean and convert everything to use the new syntax.
Signed-off-by: Donald Sharp <sharpd@cumulusnetworks.com>
We had a variety of issues with sorted list compare functions.
This commit identifies and fixes these issues.
Signed-off-by: Donald Sharp <sharpd@cumulusnetworks.com>
Allow the modification of whether or not we will allow
BUM flooding on the vxlan bridge. To do this allow
the upper level protocol to specify via the ZEBRA_VXLAN_FLOOD_CONTROL
zapi message.
If flooding is disabled then BUM traffic will not be forwarded
to other VTEP's.
Signed-off-by: Vivek Venkatraman <vivek@cumulusnetworks.com>
Signed-off-by: Donald Sharp <sharpd@cumulusnetworks.com>
The block comments from a couple commits were not following
proper style. Fix.
Fix SA warning that had snuck in.
Signed-off-by: Donald Sharp <sharpd@cumulusnetworks.com>
Ensure that when the is_router condition changes for a locally learnt
neighbor, it is informed to BGP only if it is active i.e., the MAC is
also locally learnt.
Signed-off-by: Vivek Venkatraman <vivek@cumulusnetworks.com>
Reviewed-by: Anuradha Karuppiah <anuradhak@cumulusnetworks.com>
Reviewed-by: Chirag Shah <chirag@cumulusnetworks.com>
Ticket: CM-22288
Reviewed By: CCR-7832
Testing Done:
1. Failed test
2. vxlan_routing_test.py
Use boolean variables instead of unsigned int for certain VxLAN-EVPN
flags which are really used as boolean.
Signed-off-by: Vivek Venkatraman <vivek@cumulusnetworks.com>
Reviewed-by: Anuradha Karuppiah <anuradhak@cumulusnetworks.com>
Reviewed-by: Chirag Shah <chirag@cumulusnetworks.com>
Ticket: CM-22288
Reviewed By: CCR-7832
Testing Done:
Along with a subsequent, related commit
When a remote MAC goes away, but there are neighbors referring to it,
ensure that when the last remote neighbor goes away, the MAC is
uninstalled from the kernel and no longer considered as remote.
Signed-off-by: Vivek Venkatraman <vivek@cumulusnetworks.com>
Reviewed-by: Anuradha Karuppiah <anuradhak@cumulusnetworks.com>
Reviewed-by: Chirag Shah <chirag@cumulusnetworks.com>
Ticket: CM-22130
Reviewed By: CCR-7777
Testing Done:
1. Replicated failed scenario and verified with fix.
2. evpn-min
When a MAC moves from local to remote, a replace is allowed, EVPN
no longer has to delete the local MAC before installing the remote
MAC.
Signed-off-by: Vivek Venkatraman <vivek@cumulusnetworks.com>
Reviewed-by: Anuradha Karuppiah <anuradhak@cumulusnetworks.com>
Reviewed-by: Chirag Shah <chirag@cumulusnetworks.com>
The RB-Tree used to store rmac information was not properly
handling the v6 address family. Modify the code to allow
this handling.
Cleans up this error message:
zebra[2231]: host_rb_entry_compare: Unexpected family type: 10
That is being seen, This fixes some connectivity issues being seen.
Signed-off-by: Donald Sharp <sharpd@cumulusnetworks.com>
Problem reported that some bgp and ospf json commands did not return
any json output at all if the bgp/ospf instance did not exist.
Additionally, some bgp and ospf json commands did not return any json
output if the instance existed but no neighbors were defined. This
fix makes these commands more consistent in returning empty braces for
json output and issue a message if not using json output. Additionally,
made the flag "use_json" a bool to make it consistent since previously,
it had been defined as an int, char, u_char, and bool at various places.
Ticket: CM-21040
Signed-off-by: Don Slice <dslice@cumulusnetworks.com>
Add a header to cleanup no declaration and properly
wrapper some variables to appropriate #ifdef.
Signed-off-by: Donald Sharp <sharpd@cumulusnetworks.com>
Handle Remote Neigh entry state change from Router to Host.
Remote MAC-IP update may not continue EVPN NA Extended community,
Zebra need to accomodate if router_flag change for existing neigh
and install with or without Router Flag (R-bit).
Testing:
Have locally run MAC/IP (neigh entry) with R-bit set,
Checke on remote VTEP 'show bgp evpn route ...mac ip' and
'show evpn arp-cache ...' contians router flag.
Change host to remove R-bit, which locally learnt entry removes
Router flag. This results in remote vtep to remove R-bit from
neigh entry.
Signed-off-by: Chirag Shah <chirag@cumulusnetworks.com>
Neigh update can have router_flag change, from unset to set and
viceversa. This is the case where MAC, IP and VLAN are same but
entry's flag moved from R to not R bit and reverse case.
Router flag change needs to trigger bgpd to inform all evpn peers
to remove from the evpn route.
Testing Done:
Send GARP with and without R bit from host and validate neigh entry
and evpn neigh and mac-ip route entry in zebra and bgpd.
Check Peer VTEP evpn route entry where router flag is (un)set.
With R-bit
Route [2]:[0]:[0]:[48]:[00:1f:2f:db:45:a6]:[128]:[2006:33:33:2::10]
VNI 1001
Imported from
27.0.0.16:5:[2]:[0]:[0]:[48]:[00:1f:2f:db:45:a6]:[128]:[2006:33:33:2::10]
4435 5551
27.0.0.16 from MSP1(uplink-1) (27.0.0.9)
Origin IGP, valid, external, bestpath-from-AS 4435, best
Extended Community: RT:5551:1001 ET:8 ND:Router
Flag
AddPath ID: RX 0, TX 1261
Last update: Wed Aug 15 20:52:14 2018
Without R-bit
Route [2]:[0]:[0]:[48]:[00:1f:2f:db:45:a6]:[128]:[2006:33:33:2::10]
VNI 1001
Imported from
27.0.0.16:5:[2]:[0]:[0]:[48]:[00:1f:2f:db:45:a6]:[128]:[2006:33:33:2::10]
4435 5551
27.0.0.16 from MSP2(uplink-2) (27.0.0.10)
Origin IGP, valid, external, bestpath-from-AS 4435, best
Extended Community: RT:5551:1001 ET:8
AddPath ID: RX 0, TX 1263
Last update: Wed Aug 15 20:53:10 2018
Signed-off-by: Chirag Shah <chirag@cumulusnetworks.com>
The neigh update can come prior to mac add update.
In this case, the mac will be auto created for the vni.
set router flag to local neigh update for mac with auto flag.
The neigh update will be informed to bgpd once local mac is learnt.
Unset router flag if the neigh update comes without the router flag
for an existing neigh entry.
Signed-off-by: Chirag Shah <chirag@cumulusnetworks.com>
Enhance the EVPN MAC and Neighbor cache display to show additional
information such as the mobility sequence numbers and the state.
Ensure that the neighbor state is set in a couple of places so
that the display is correct.
Signed-off-by: Vivek Venkatraman <vivek@cumulusnetworks.com>
Implement procedures similar to what is specified in
https://tools.ietf.org/html/draft-malhotra-bess-evpn-irb-extended-mobility
in order to support extended mobility scenarios in EVPN. These are scenarios
where a host/VM move results in a different (MAC,IP) binding from earlier.
For example, a host with an address assignment (IP1, MAC1) moves behind a
different PE (VTEP) and has an address assignment of (IP1, MAC2) or a host
with an address assignment (IP5, MAC5) has a different assignment of (IP6,
MAC5) after the move. Note that while these are described as "move" scenarios,
they also cover the situation when a VM is shut down and a new VM is spun up
at a different location that reuses the IP address or MAC address of the
earlier instance, but not both. Yet another scenario is a MAC change for an
attached host/VM i.e., when the MAC of an attached host changes from MAC1 to
MAC2. This is necessary because there may already be a non-zero sequence
number associated with MAC2. Also, even though (IP, MAC1) is withdrawn before
(IP, MAC2) is advertised, they may propagate through the network differently.
The procedures continue to rely on the MAC mobility extended community
specified in RFC 7432 and already supported by the implementation, but
augment it with a inheritance mechanism that understands the relationship
of the host MACIP (ARP/neighbor table entry) to the underlying MAC (MAC
forwarding database entry). In FRR, this relationship is understood by the
zebra component which doubles as the "host mobility manager", so the MAC
mobility sequence numbers are determined through interaction between bgpd
and zebra.
Signed-off-by: Vivek Venkatraman <vivek@cumulusnetworks.com>
Reviewed-by: Donald Sharp <sharpd@cumulusnetworks.com>
Reviewed-by: Anuradha Karuppiah <anuradhak@cumulusnetworks.com>
When a host moves and is locally reachable, if the local neighbor event
is received before the local MAC event, flag the neighbor as inactive
just as would happen in the case of a new host. This ensures that the
MACIP route will get originated as soon as the local MAC event is got.
Signed-off-by: Vivek Venkatraman <vivek@cumulusnetworks.com>