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Basic Switch Configuration
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authentication or permission-based file access authorization. It ensures correct data
transmission by sending and acknowledging mechanism and retransmission of time-out
packets. The advantage of TFTP over FTP is that it is a simple and low overhead file
transfer service.
Switch can operate as either FTP/TFTP client or server. When switch operates as a
FTP/TFTP client, configuration files or system files can be downloaded from the remote
FTP/TFTP servers (can be hosts or other switches) without affecting its normal operation.
And file list can also be retrieved from the server in ftp client mode. Of course, switch can
also upload current configuration files or system files to the remote FTP/TFTP servers
(can be hosts or other switches). When switch operates as a FTP/TFTP server, it can
provide file upload and download service for authorized FTP/TFTP clients, as file list
service as FTP server.
Here are some terms frequently used in FTP/TFTP.
ROM:
Short for EPROM, erasable read-only memory. EPROM is repalced by FLASH
memory in switch.
SDRAM:
RAM memory in the switch, used for system software operation and
configuration sequence storage.
FLASH:
Flash memory used to save system file and configuration file.
System file:
including system image file and boot file.
System image file:
refers to the compressed file for switch hardware driver and software
support program, usually refer to as IMAGE upgrade file. In switch, the system image file
is allowed to save in FLASH only. Switch mandates the name of system image file to be
uploaded via FTP in Global Mode to be nos.img, other IMAGE system files will be
rejected.
Boot file:
refers to the file initializes the switch, also referred to as the ROM upgrade file
(Large size file can be compressed as IMAGE file). In switch, the boot file is allowed to
save in ROM only. Switch mandates the path and the name of two boot files to be
flash:/boot.rom and flash:/config.rom.
Configuration file:
including start up configuration file and running configuration file. The
distinction between start up configuration file and running configuration file can facilitate
the backup and update of the configurations.
Start up configuration file:
refers to the configuration sequence used in switch startup.
Startup configuration file stores in nonvolatile storage, corresponding to the so-called
configuration save. If the device does not support CF, the configuration file stores in
FLASH only, if the device supports CF, the configuration file stores in FLASH or CF, if the
device supports multi-config file, names the configuration file to be .cfg file, the default is
startup.cfg. If the device does not support multi-config file, mandates the name of startup
configuration file to be startup-config.