// Internal control command.
// Migrate moves one slot data to another server on the fly.
func (c *CtrlContext) Migrate(host string, slotId uint16) error {
call := c.cli.newCall(proto.CmdMigrate, nil)
if call.err != nil {
return call.err
}
var p ctrl.PkgMigrate
p.ClientReq = true
p.MasterAddr = host
p.SlotId = slotId
pkg, err := ctrl.Encode(call.cmd, c.dbId, call.seq, &p)
if err != nil {
c.cli.errCall(call, err)
return err
}
call.pkg = pkg
c.cli.sending <- call
r, err := (<-call.Done).Reply()
if err != nil {
return err
}
t := r.(*ctrl.PkgMigrate)
if t.ErrMsg != "" {
return errors.New(t.ErrMsg)
}
return nil
}
func (slv *slave) SendSlaveOfToMaster() error {
slv.mtx.Lock()
var mi = slv.mi
var cli = slv.cli
slv.mtx.Unlock()
if cli == nil {
return nil
}
var err error
var pkg []byte
if mi.Migration {
var p ctrl.PkgMigrate
p.ClientReq = false
p.MasterAddr = mi.MasterAddr
p.SlaveAddr = mi.SlaveAddr
p.SlotId = mi.SlotId
pkg, err = ctrl.Encode(proto.CmdMigrate, 0, 0, &p)
if err != nil {
return err
}
} else {
lastSeq, valid := slv.bin.GetMasterSeq()
if !valid {
slv.mc.SetStatus(ctrl.SlaveNeedClear)
// Any better solution?
log.Fatalf("Slave lastSeq %d is out of sync, please clear old data! "+
"(Restart may fix this issue)", lastSeq)
}
var p ctrl.PkgSlaveOf
p.ClientReq = false
p.MasterAddr = mi.MasterAddr
p.SlaveAddr = mi.SlaveAddr
p.LastSeq = lastSeq
log.Printf("Connect to master %s with lastSeq %d\n",
mi.MasterAddr, p.LastSeq)
pkg, err = ctrl.Encode(proto.CmdSlaveOf, 0, 0, &p)
if err != nil {
return err
}
}
cli.AddResp(pkg)
return slv.mc.SetStatus(ctrl.SlaveFullSync)
}
