pve5to6 fails with "Unsupported SSH Cipher configured for root in /root/.ssh/config: 3des"


Renowned Member
May 7, 2015
trying to upgrade from version 5. 4-2 to 6, using pve5to6 script fail returning error: "Unsupported SSH Cipher configured for root in /root/.ssh/config: 3des"

cat /root/.ssh/config
Ciphers blowfish-cbc,aes128-ctr,aes192-ctr,aes256-ctr,arcfour256,arcfour128,aes128-cbc,3des-cbc

thanks in advance for help
remove the file (to use the built-in default of openssh) or replace it with more modern ciphers
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Hallo @fabian
i had the same error and only removed the last part ,3des-cbc
then i had a problem with arcfour

so you mean to remove the hole file ?

have a nice day

No not the file just the cipher list line so it will use defaults, or also remove arcfour

The issue is due to them being removed in Debian10


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