通过vtysh的多个配置命令

I have device configuration saved in a file and use it to configure through vtysh.

config,err := ioutil.ReadFile(filePath)
if err != nil {
    fmt.Println("Read err:")
    fmt.Println(err)
    os.Exit(1)
}
cmd := exec.Command("vtysh", "-c", "configure terminal", "-c",string(config))
out, err := cmd.CombinedOutput()
if err != nil {
    fmt.Println("vtysh err:")
    fmt.Println(err)
    return
} else {
    fmt.Println(out)
}

Above code gives error:

vtysh err:
exit status 1

File contents :

vlan 1
    no shutdown
vlan 999
    no shutdown

If I paste the file contents into vtysh( config terminal context) then the commands do execute.

The vtysh commands that I'm trying to run:

switch# configure terminal
switch(config)# vlan 89
switch(config-vlan)# no shut
switch(config-vlan)# vlan 90
switch(config-vlan)# no shut