bonding mode changing automatically between reboots

[mad Engineer]

i am running ubuntu 14.04 with interfaces in LACP bonded mode.

cat /etc/network/interfaces.d/ifcfg-bond0
auto bond0
iface bond0 inet manual
bond-slaves eth6 eth8
bond-mode 802.3ad
bond-miimon 100
bond-lacp-rate fast
bond-updelay 200
bond-downdelay 200
bond-ad-select bandwidth
bond-xmit-hash-policy layer2+3
post-up sleep 4


But after reboot bonding algorithm changes to Round Robin

cat /proc/net//bonding/bond0
Ethernet Channel Bonding Driver: v3.7.1 (April 27, 2011)

Bonding Mode: load balancing (round-robin)
MII Status: up
MII Polling Interval (ms): 100
Up Delay (ms): 200
Down Delay (ms): 200

Slave Interface: eth6
MII Status: up
Speed: 10000 Mbps
Duplex: full
Link Failure Count: 0
Permanent HW addr: a0:36:9f:72:f1:e0
Slave queue ID: 0

Slave Interface: eth8
MII Status: up
Speed: 10000 Mbps
Duplex: full
Link Failure Count: 0
Permanent HW addr: a0:36:9f:72:f7:f8
Slave queue ID: 0


If i reboot again it will change back to LACP that too with out making
any configuration changes.

modinfo bonding
filename:
/lib/modules/3.13.0-61-generic/kernel/drivers/net/bonding/bonding.ko
author:         Thomas Davis, tadavis at lbl.gov and many others
description:    Ethernet Channel Bonding Driver, v3.7.1
version:        3.7.1
license:        GPL
alias:          rtnl-link-bond
srcversion:     D3CB797CA8EB816C8BA298D
depends:
intree:         Y
vermagic:       3.13.0-61-generic SMP mod_unload modversions
signer:         Magrathea: Glacier signing key
sig_key:        B2:62:66:63:38:5C:77:0E:C7:E3:84:A8:90:9C:CD:47:C2:D2:00:E1
sig_hashalgo:   sha512
parm:           max_bonds:Max number of bonded devices (int)
parm:           tx_queues:Max number of transmit queues (default = 16) (int)
parm:           num_grat_arp:Number of peer notifications to send on
failover event (alias of num_unsol_na) (int)
parm:           num_unsol_na:Number of peer notifications to send on
failover event (alias of num_grat_arp) (int)
parm:           miimon:Link check interval in milliseconds (int)
parm:           updelay:Delay before considering link up, in milliseconds (int)
parm:           downdelay:Delay before considering link down, in
milliseconds (int)
parm:           use_carrier:Use netif_carrier_ok (vs MII ioctls) in
miimon; 0 for off, 1 for on (default) (int)
parm:           mode:Mode of operation; 0 for balance-rr, 1 for
active-backup, 2 for balance-xor, 3 for broadcast, 4 for 802.3ad, 5
for balance-tlb, 6 for balance-alb (charp)
parm:           primary:Primary network device to use (charp)
parm:           primary_reselect:Reselect primary slave once it comes
up; 0 for always (default), 1 for only if speed of primary is better,
2 for only on active slave failure (charp)
parm:           lacp_rate:LACPDU tx rate to request from 802.3ad
partner; 0 for slow, 1 for fast (charp)
parm:           ad_select:803.ad aggregation selection logic; 0 for
stable (default), 1 for bandwidth, 2 for count (charp)
parm:           min_links:Minimum number of available links before
turning on carrier (int)
parm:           xmit_hash_policy:balance-xor and 802.3ad hashing
method; 0 for layer 2 (default), 1 for layer 3+4, 2 for layer 2+3, 3
for encap layer 2+3, 4 for encap layer 3+4 (charp)
parm:           arp_interval:arp interval in milliseconds (int)
parm:           arp_ip_target:arp targets in n.n.n.n form (array of charp)
parm:           arp_validate:validate src/dst of ARP probes; 0 for
none (default), 1 for active, 2 for backup, 3 for all (charp)
parm:           arp_all_targets:fail on any/all arp targets timeout; 0
for any (default), 1 for all (charp)
parm:           fail_over_mac:For active-backup, do not set all slaves
to the same MAC; 0 for none (default), 1 for active, 2 for follow
(charp)
parm:           all_slaves_active:Keep all frames received on an
interfaceby setting active flag for all slaves; 0 for never (default),
1 for always. (int)
parm:           resend_igmp:Number of IGMP membership reports to send
on link failure (int)
parm:           packets_per_slave:Packets to send per slave in
balance-rr mode; 0 for a random slave, 1 packet per slave (default),
>1 packets per slave. (int)



any idea?