Backup database to multiple files

backup database msdb
to
disk = 'C:\temp\msdb_1.bak',
disk = 'C:\temp\msdb_2.bak',
disk = 'C:\temp\msdb_3.bak',
disk = 'C:\temp\msdb_4.bak',
disk = 'C:\temp\msdb_5.bak',
disk = 'C:\temp\msdb_6.bak',
disk = 'C:\temp\msdb_7.bak',
disk = 'C:\temp\msdb_8.bak'