it happens on this node (Master, mvebu, cortex-A9) only with ifup wan.
log
40:49 netifd: Interface 'wan' is enabled
40:49 kernel: [ 4539.310854] mvneta f1034000.ethernet eth2: configuring for inband/1000base-x link mode
40:49 kernel: [ 4539.629747] sfp sfp: module transmit fault indicated
40:51 netifd: Network device 'eth2' link is up
40:51 netifd: Interface 'wan' has link connectivity
40:51 netifd: Interface 'wan' is setting up now
40:51 kernel: [ 4541.699901] mvneta f1034000.ethernet eth2: Link is Up - 1Gbps/Full - flow control off
40:51 kernel: [ 4541.699917] IPv6: ADDRCONF(NETDEV_CHANGE): eth2: link becomes ready
40:51 insmod: module is already loaded - slhc
40:51 insmod: module is already loaded - ppp_generic
40:51 insmod: module is already loaded - pppox
40:51 insmod: module is already loaded - pppoe
40:51 pppd[29207]: Plugin rp-pppoe.so loaded.
40:51 pppd[29207]: RP-PPPoE plugin version 3.8p compiled against pppd 2.4.8
40:51 pppd[29207]: pppd 2.4.8 started by root, uid 0
41:06 pppd[29207]: Timeout waiting for PADO packets
41:06 pppd[29207]: Unable complete PPPoE Discovery
41:06 pppd[29207]: Exit.
41:06 netifd: Interface 'wan' is now down
41:06 kernel: [ 4556.940117] mvneta f1034000.ethernet eth2: Link is Down
41:06 netifd: Interface 'wan' is disabled
41:06 netifd: Interface 'wan' is enabled
41:06 netifd: Interface 'wan' is setting up now
41:06 kernel: [ 4556.954502] mvneta f1034000.ethernet eth2: configuring for inband/1000base-x link mode
41:06 netifd: Network device 'eth2' link is down
41:06 netifd: Interface 'wan' has link connectivity loss
41:06 insmod: module is already loaded - slhc
41:06 insmod: module is already loaded - ppp_generic
41:06 insmod: module is already loaded - pppox
41:06 insmod: module is already loaded - pppoe
41:07 netifd: wan (29306): Command failed: Permission denied
41:07 netifd: Interface 'wan' is now down
41:07 netifd: Interface 'wan' is disabled
41:07 netifd: Interface 'wan' is enabled
41:07 kernel: [ 4557.042474] mvneta f1034000.ethernet eth2: configuring for inband/1000base-x link mode
41:07 netifd: Network device 'eth2' link is up
41:07 netifd: Interface 'wan' has link connectivity
41:07 netifd: Interface 'wan' is setting up now
41:07 kernel: [ 4557.209931] mvneta f1034000.ethernet eth2: Link is Up - 1Gbps/Full - flow control off
41:07 kernel: [ 4557.209948] IPv6: ADDRCONF(NETDEV_CHANGE): eth2: link becomes ready
41:07 insmod: module is already loaded - slhc
41:07 insmod: module is already loaded - ppp_generic
41:07 insmod: module is already loaded - pppox
41:07 insmod: module is already loaded - pppoe
41:07 pppd[29362]: Plugin rp-pppoe.so loaded.
41:07 pppd[29362]: RP-PPPoE plugin version 3.8p compiled against pppd 2.4.8
41:07 pppd[29362]: pppd 2.4.8 started by root, uid 0
41:22 pppd[29362]: Timeout waiting for PADO packets
41:22 pppd[29362]: Unable complete PPPoE Discovery
41:22 pppd[29362]: Exit.
41:22 netifd: Interface 'wan' is now down
41:22 kernel: [ 4572.446438] mvneta f1034000.ethernet eth2: Link is Down
41:22 netifd: Interface 'wan' is disabled
41:22 netifd: Interface 'wan' is enabled
41:22 netifd: Interface 'wan' is setting up now
41:22 netifd: Network device 'eth2' link is down
41:22 netifd: Interface 'wan' has link connectivity loss
41:22 kernel: [ 4572.459786] mvneta f1034000.ethernet eth2: configuring for inband/1000base-x link mode
41:22 insmod: module is already loaded - slhc
41:22 insmod: module is already loaded - ppp_generic
41:22 insmod: module is already loaded - pppox
41:22 insmod: module is already loaded - pppoe
41:22 netifd: wan (29492): Command failed: Permission denied
41:22 netifd: Interface 'wan' is now down
41:22 netifd: Interface 'wan' is disabled
41:22 netifd: Interface 'wan' is enabled
41:22 kernel: [ 4572.544765] mvneta f1034000.ethernet eth2: configuring for inband/1000base-x link mode
41:22 netifd: Network device 'eth2' link is up
41:22 netifd: Interface 'wan' has link connectivity
41:22 netifd: Interface 'wan' is setting up now
41:22 kernel: [ 4572.712631] mvneta f1034000.ethernet eth2: Link is Up - 1Gbps/Full - flow control off
41:22 kernel: [ 4572.712647] IPv6: ADDRCONF(NETDEV_CHANGE): eth2: link becomes ready
41:22 insmod: module is already loaded - slhc
41:22 insmod: module is already loaded - ppp_generic
41:22 insmod: module is already loaded - pppox
41:22 insmod: module is already loaded - pppoe
41:22 pppd[29549]: Plugin rp-pppoe.so loaded.
41:22 pppd[29549]: RP-PPPoE plugin version 3.8p compiled against pppd 2.4.8
41:22 pppd[29549]: pppd 2.4.8 started by root, uid 0
41:29 pppd[29549]: PPP session is 31713
41:29 pppd[29549]: Connected 78:ba:f9:73:f5:74 via interface eth2
41:29 kernel: [ 4579.318874] pppoe-wan: renamed from ppp0
41:29 pppd[29549]: Renamed interface ppp0 pppoe-wan
41:29 pppd[29549]: Using interface pppoe-wan
41:29 pppd[29549]: Connect: pppoe-wan <--> eth2
41:35 pppd[29549]: PAP authentication succeeded
41:35 pppd[29549]: peer from calling number 78:BA:F9:73:F5:74 authorized
41:35 pppd[29549]: local IP address
41:35 pppd[29549]: remote IP address
41:35 pppd[29549]: primary DNS address
41:35 pppd[29549]: secondary DNS address
41:35 pppd[29549]: local LL address fe80::b931:4e21:f7f2:a0ad
41:35 pppd[29549]: remote LL address fe80::7aba:f9ff:fe73:f574
41:35 netifd: Network device 'pppoe-wan' link is up
41:35 netifd: Interface 'wan' is now up
41:35 netifd: Network alias 'pppoe-wan' link is up
41:35 netifd: Interface 'wan_6' is enabled
41:35 netifd: Interface 'wan_6' has link connectivity
41:35 netifd: Interface 'wan_6' is setting up now