Two s9306 make vrrp master and backup，address is：
Two swtich versions are s9300 v100r001c02b118，to upgrade v100r001c02b125，it needs to copy the upgrade packet to device afcard by ftp command，login s9306-1 by 192.168.1.81 address，it found that cannot transmit data，login s9306-2 by 192.168.1.83 address，it found that can transmit data.
ftp login s9306-1，inport put or get command，warn information is as follows：
200 port command okay.
425 can't open data connection
1. Use command ftp 192.168.1.81 to login s9306-1，found that the address cannot transmit data
2. Use command ftp192.168.1.83 to login s9306-2，it can transmit files normally
3. compare the difference between 2 command：192.168.1.81 is vrrp virtual address，adoubt that the virtual address does not support ftp file transmission.
4. Import the command ftp 192.168.1.82, in ftp client side（pc），it can transmit data after login s9306-1.
192.168.1.81 is vrrp virtual address，bit vrrp address does not support ftp file transmission