C3650, does this switch appear to be reset?

[DH2025]

Greetings,

I have aquired a second hand WS-C3650-8X24UQ-S. Appears to be working as is (connected to router and one pc), and no password. 

When looking up reset instructions, I see typically you flash_init, then delete config.text and vlan.dat (after holding mode button)

Once I flash_init, the directory does not include these two files. I'll attach a picture of the directory.

It appears that this switch has been reset using that method already, am I correct? 

Thanks for your time.

 

[Leo Laohoo]

To factory-reset the switch, use the following command: 

factory-reset all

This command will wipe the flash (and other partitions), including the OS.

[DH2025]

Hello Leo, thank you for your reply. I don't want to factory reset (and wipe OS). I just wish to wipe any configurations relating to the switch and start fresh with the currently installed OS. Does it appear the previous owner did this, based on those two files not being the directory I shared?

[Leo Laohoo]

Then use the command "factory-reset config" only to wipe the config off the switch.

[Jens Albrecht]

Hello @DH2025,

the file 'config.text' that you look for in the flash: does no longer exist on IOS-XE devices. What you mentioned refers to the old IOS switches where you could see such file in the flash: with the same size as the 'startup-config' in nvram:

So you can only check for the existence of the 'vlan.dat' file on the flash: while the config file can only be seen in the nvram: (technically it is contained in the much larger file 'nvram_config' which you should not touch at all).

Since there is no password on your switch, the 'factory-reset' command mentioned by Leo is the best way to clean up the device.

HTH!

[DH2025]

Thank you for both of your replies. That clears things up a bit for me.

For the ""factory-reset config" command, do I need to be in that boot interupted mode (holding mode at startup) or can I perform the command during normal switch operation? Also once I perform the command do I need to do anything else like a "reload" or "boot" command?

I had two other questions if you both wouldn't mind helping out.

Do I need to go through that initial configuration setup once I reset the config or will the switch still operate as is? (For reference this switch doesn't need to do anything but essentially operate as an unmanaged switch.)

Also, would anything be slowing down connection establishment between devices and the switch, I notice when I boot up my PC it takes about maybe half a minute or so for a connection to be established in the switches current status. On previous switches by the time the PC booted up, a connection was already established. Connection is fine once established.

Again, I really appreciate everyone's assistance, thank you

[Leo Laohoo]

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@DH2025 wrote:
For the ""factory-reset config" command, do I need to be in that boot interupted mode (holding mode at startup) or can I perform the command during normal switch operation? Also once I perform the command do I need to do anything else like a "reload" or "boot" command?

---

The command "factory-reset config" can be used in enable mode only. 

For "consistency" (or lack of) purposes, the command "factory-reset all" is implemented differently in different platforms and the behaviour varies in different firmware version.   For example, when used on switches like 3650/3850, 9200/9500 (I have no access to 9400/9600 supervisor line cards), entering this command will wipe the entire flash, including the firmware, including some (if not all) of the read-only partition.  The switch will boot into ROMMON because the firmware is completely wiped out.   And, depending on the ROMMON or micro-code version running on the switch, the command "emergency-install usbflash0:" may no longer work with newer ROMMON or micro-code version.  

When used on a 9800, the firmware is copied and stored in a read-only partition while the rest of the flash is wiped out.  After the process is completed, the firmware is moved back to the main bootflash and the WLC is able to boot into the OS.  

[DH2025]

Thank you for this info. I wanted to avoid losing the OS, so I am thankful for you pointing out the factory-reset config command. I successfully wiped the configs using that command. Thanks again!

[Jens Albrecht]

Leo already answered your question regarding the factory-reset command so let's take a look at those "two other questions":

#1) After a factory reset (or if you take a new device out of the box) Cisco switches will use default values that allow you to use them pretty much like an unmanaged switch. This means that there is only vlan 1 and all ports are assigned to this vlan. You can plug hosts into this switch and they will be able to communicate using vlan 1. You can also connect a router to one of the ports so that the host can reach their gateway. So no need to go through the initial setup if this is what you want.

#2) The above mentioned default values after factory-reset are also the reason for the 30 seconds delay when connecting a host. Cisco runs STP by default and when you connect a host, the forward-delay timer of STP (default 30 seconds) starts to check whether or not the switch receives any BPDUs on this port. You can see this when looking at the port LED. When you connect a host it shines amber first and after 30 seconds it turns green and the port starts forwarding traffic.

The easiest way to change this behavior is using the global command 'spanning-tree portfast default' which activates portfast on all non-trunking ports. Then those ports will become active as soon as you plug in any device.

HTH!

[DH2025]

Hello Jens

Thank you for replying back to me. I'll clear some configs and VLANs I played around with this past week so the switch is back to default again. Then I'll try that "spanning-tree portfast default" command to see if connection times normalize. I'll report back if I have any issues.

Thanks again!

[DH2025]

Hello Jens,

You suggestion worked. I get connections instantly. I have since wired in the rest of my network to the switch and I've had no issues so far in the last two weeks.

When I activated 'spanning-tree portfast default', I got a warning to turn off portfast explicitly on switched ports leading to hubs, switches, and bridges as they may create temporary bridging loops. I have portfast active on all ports, including those leading to unmanaged switches and wireless access points. Will this eventually give me any issues or will I be fine as is?

Thanks again for your help!

[Jens Albrecht]

Hello @DH2025,

glad to hear it's working.

The warning that you see when activating spanning-tree portfast is just a friendly reminder.

If you plug in a switch by mistake this will cause a temporary loop. However, as soon as the switch receives a BPDU frame from the new neighbor, it will disable portfast and go through the regular spanning-tree stages to decide whether this port should be blocked or not.

So it is fine as is and the switch will take care of breaking any switching loops in case they occur.

HTH and please do not forget to mark posts as solutions if your questions got answered. Thanks!