How to clean up configuration Huawei switch ? I use the switch Huawei S9306 in my network. [Y/N]:y reboot Warning: All the configuration will be saved to the configuration file for the n ext startup:, Continue?[Y/N]:n // At this time need choose n, if choose y the former configuration will save, restart is still the original configuration. Why?

yes you can upload configuration file on S5300 switch flash using serial connection. Please check below link. is an upgrade guide for deploying a system software. it shows you how to upload system software to the flash, the process is the same for configuration file.
it is possible to connect a laptop to the switch? Ethernet cable, configure ip addresses, enable ftp, configure ftp user and then upload to file to the switch via ethernet?

To solve this problem, configure the service port of the switch connected to the diskless workstation as an edge port. For details, see the user guide of the web network management system. Huawei Networking Products News and FAQ

It's different from configuring rate limit for Huawei S6700 and other Huawei Swithes. The article as below may help you for your question
Huawei Networking Products News and FAQ

reset saved-configuration
then reboot

NCK code Or Network Unlock code all are same Only.You can get the Huawei U7510 Model NCK code from here
Theunlockspot.com
and get the Unlocking instructions there or follow it below and Unlock it step by step..


Huawei U7510 Unlocking Instructions Warning : Do not enter any wrong unlock codes on your Huawei U7510 mobile phones. If you enter over a certain amount of wrong unlock codes on your Huawei U7510 mobile phone, your phone may get hard locked and sometimes become unusable.
If your Huawei Device is a mobile phone:

1.Switch on your Huawei Phone using another networks SIM card.
2.Your phone should ask for an unlock code(NCK Code).
3. Enter the unlock code we sent you.

To get the NP code for the Huawei G6600 model Phone You can reach here
Theunlockspot buy the code at reasonable cost and Unlock it from Network provider lock,then NP code means Network provider or Unlock code to remove the Network lock,after Unlock Your HUAWEI G6600 you can use any GSM Network Sim in the Phone......To Unlock it follow the steps or instructions below:

Huawei G6600 Unlocking Instructions Warning : Do not enter any wrong unlock codes on your Huawei G6600 mobile phones. If you enter over a certain amount of wrong unlock codes on your Huawei G6600 mobile phone, your phone may get hard locked and sometimes become unusable.
If your Huawei Device is a mobile phone:

1.Switch on your Huawei Phone using another networks SIM card.
2.Your phone should ask for an unlock code(NCK Code).
3. Enter the unlock code we sent you.