[j-nsp] ex4200 vc reboot master - perplexed

[ryanL]

hi all. relatively new to juniper gear, very new to virtual chassis.

have 2x ex4200 top of rack in vc. bare bones config. connected to two
core 4500's, not doing vc. also not doing spanning-tree (no need).
vrrp is on c1 and c2 for the rack subnet, formed via the 4200's. sorry
if my bad ascii art doesn't format proper.

c1-----ospf------c2
|				|
|				|
|				|
4200a-----vc----4200b

i have a host hanging off the 4200's. when i reload the master 4200a,
i see the mac address instantaneously get removed on c1, show up on
c2, via 4200b. makes sense. i also see vrrp mastership flip to c2,
which is done via link-tracking. why, then, do i see ~45s of data loss
to the host? it seems to be 45s pretty much every time i punt.

to test this i'm pinging the host from c1 and c2 simultaneously.

the host is doing bond0, active/backup. it flips over properly when
the active side fails.

is there something special about vc that i'm missing? i enabled
no-split-detection because without it was really really bad news.

appreciate any insight or things to look for!

ryanL


root at fsad-rs1> show configuration virtual-chassis
no-split-detection;
member 0 {
    mastership-priority 200;
}
member 1 {
    mastership-priority 200;
}

{master:1}
root at fsad-rs1> show virtual-chassis status

Virtual Chassis ID: 2ecd.820c.7baf
Virtual Chassis Mode: Enabled
                                           Mstr           Mixed Neighbor List
Member ID  Status   Serial No    Model     prio  Role      Mode ID  Interface
0 (FPC 0)  Prsnt    BP0212245349 ex4200-48t 200  Backup       N  1  vcp-0
                                                                 1  vcp-1
1 (FPC 1)  Prsnt    BP0212245335 ex4200-48t 200  Master*      N  0  vcp-0
                                                                 0  vcp-1

Member ID for next new member: 2 (FPC 2)

{master:1}

root at fsad-rs1> show version
fpc0:
--------------------------------------------------------------------------
Hostname: fsad-rs1
Model: ex4200-48t
JUNOS Base OS boot [11.4R2.14]
JUNOS Base OS Software Suite [11.4R2.14]
JUNOS Kernel Software Suite [11.4R2.14]
JUNOS Crypto Software Suite [11.4R2.14]
JUNOS Online Documentation [11.4R2.14]
JUNOS Enterprise Software Suite [11.4R2.14]
JUNOS Packet Forwarding Engine Enterprise Software Suite [11.4R2.14]
JUNOS Routing Software Suite [11.4R2.14]
JUNOS Web Management [11.4R2.14]

fpc1:
--------------------------------------------------------------------------
Hostname: fsad-rs1
Model: ex4200-48t
JUNOS Base OS boot [11.4R2.14]
JUNOS Base OS Software Suite [11.4R2.14]
JUNOS Kernel Software Suite [11.4R2.14]
JUNOS Crypto Software Suite [11.4R2.14]
JUNOS Online Documentation [11.4R2.14]
JUNOS Enterprise Software Suite [11.4R2.14]
JUNOS Packet Forwarding Engine Enterprise Software Suite [11.4R2.14]
JUNOS Routing Software Suite [11.4R2.14]
JUNOS Web Management [11.4R2.14]