Install own SSL certificate on PowerConnect 62xx

Hello all,

I want to install self-signed certificates on 6248 switch. Dell support engineer recommended the following:

"generated Key+CSR with OpenSSL in RSA 2048Bit SHA-256.The naming of the key on the switch is sslt_key1.pem and the cert is sslt_cert1.pem. Copy these files to flash:// and they override the existing ones, reload the website and it's working."

My problem is that I can't copy sslt_key1.pem and the sslt_cert1.pem files to the switch. When I try to (Dell forum editor doesn't allow me to enter t f t p prefix, but be sure I entered it there):

SWITCH#copy ://192.168.0.1/sslt_key1.pem sslt_key1.pem

I'm getting % Invalid input detected at '^' marker. ^ points to the second 's' in last sslt_key1.pem word.

I tried to do this using web interface - there are a lot of options: SSH-1 RSA key file, SSH2 RSA key PEM file, etc. 7 different options. Which one to use - is not clear.

I was able to generate certificates in "usual" way on the switch itself, but then the Firefox complains SEC_ERROR_REUSED_ISSUER_AND_SERIAL - I suppose that two my Dell switches uses the same ISSUER and SERIAL number when makes certificates.

I'm using latest firmware - 3.3.17.0.

To summarize my questions:
1. how to copy sslt*.pem files from my machine to 62xx switch (using ftfp preferably)?
2. is it possible to solve SEC_ERROR_REUSED_ISSUER_AND_SERIAL error in Firefox if I have 4 switches?

Thanks in advance,
Nikolai