GNS3 - not enough space on flash to store vlan database

If you want to emulate the switch on GNS3 or EVE-NG, you need to equip the C3600 or C3700 router with the EtherSwitch Network Module (ESW) - NM-15ESW.

However, the problem arises when configuring the VLAN after turning on the router.
When creating a VLAN as shown below, an error occurs saying that the flash memory storage space is insufficient to store the VLAN database.


SW1#vlan database
SW1(vlan)#vlan 12
VLAN 12 added:
  Name: VLAN0012


SW1(vlan)#apply
% not enough space on flash to store vlan database. trying squeeze...
% error squeezing flash - (Bad boot sector, format recommended)
Error on database apply 40: NV storage failure


SW1(vlan)#exit
% not enough space on flash to store vlan database. trying squeeze...
% error squeezing flash - (Bad boot sector, format recommended)
Error on database apply 40: NV storage failure
Use 'abort' command to exit

SW1(vlan)#abort
Aborting....

● Here is a way to fix this problem:

▶ Increase PCMCIA disk size on GNS3 Node Properties

Right click on the router (e.g. C3640, C3725) you added, Configure, and go to the Memories and disks menu.



Increase the PCMCIA disk0, disk1 size to 1 MiB from 0. Click Apply and OK.


Start your router again.

You will get the above error - "not enough space on flash to store vlan database" again. If not, you are lucky.


Here are a few more steps to fix this issue.

▶ Erase Flash now from the privilege mode (#).

SW1#erase flash:
Erasing the flash filesystem will remove all files! Continue? [confirm]
%Error erasing flash: (Bad boot sector, format recommended)
SW1#

If erasing flash works, then you are good to go. If not, try 'format flash:' command.

SW1#format flash:
Format operation may take a while. Continue? [confirm]
Format operation will destroy all data in "flash:". Continue? [confirm]
Format: Drive communication & 1st Sector Write OK...
Writing Monlib sectors.........................................................................................
Monlib write complete

Format: All system sectors written. OK...

Format: Total sectors in formatted partition: 1926
Format: Total bytes in formatted partition: 986112
Format: Operation completed successfully.

Format of flash complete


And then try 'erase flash:' command again.

SW1#erase flash:
Erasing the flash filesystem will remove all files! Continue? [confirm]
Current DOS File System flash card in flash: will be formatted into Low End File System flash card! Continue? [confirm]
Erasing device... eeeeeeeeeeeeeeee ...erased
Erase of flash: complete


All set! Now you should be able to create VLANs without the error.


SW1#vlan database
SW1(vlan)#vlan 12
VLAN 12 added:
  Name: VLAN0012
SW1(vlan)#apply
APPLY completed.
SW1(vlan)#exit
APPLY completed.
Exiting....
SW1#

Hope this helps!