VCF on VxRail: Backup Configuration Fails with Invalid Parameter
Summary: Backup configuration fails with invalid parameter: Validation failed for directory path. Please make sure backup directory is intact and the SFTP server has write permissions on the backup path. ...
This article applies to
This article does not apply to
This article is not tied to any specific product.
Not all product versions are identified in this article.
Symptoms
After a user applies the SFTP backup configuration, a user may see that the following error is returned:
Invalid parameter: Validation failed for directory path /path/to/backup/location" on server sftp.domain.com. Please make sure backup directory is intact and sftp server has write permissions on backup path.

Domainmanager.log shows the following error:
2023-02-14T14:01:06.035+0000 DEBUG [vcf_om,8afed32d4e774023,5787] [c.v.e.s.c.u.InMemoryHostKeyRepository,http-nio-127.0.0.1-7300-exec-10] Key <hidden> of type ecdsa-sha2-nistp256 for host sftp.domain.com not found in [KeySpec(host=sftp.domain.com, port=Optional[22], keyType=ssh-rsa, key=<hidden>)]
Cause
Checking the Signature Algorithms supported by the SFTP server, a user sees that SSH-RSA is not supported, due to the security policy set:
[centos-admin@CENTOS-9 ~]$ cat /etc/crypto-policies/back-ends/openssh.config Ciphers aes256-gcm@openssh.com,chacha20-poly1305@openssh.com,aes256-ctr,aes256-cbc,aes128-gcm@openssh.com,aes128-ctr,aes128-cbc MACs hmac-sha2-256-etm@openssh.com,hmac-sha1-etm@openssh.com,umac-128-etm@openssh.com,hmac-sha2-512-etm@openssh.com,hmac-sha2-256,hmac-sha1,umac-128@openssh.com,hmac-sha2-512 GSSAPIKexAlgorithms gss-curve25519-sha256-,gss-nistp256-sha256-,gss-group14-sha256-,gss-group16-sha512-,gss-gex-sha1-,gss-group14-sha1- KexAlgorithms curve25519-sha256,curve25519-sha256@libssh.org,ecdh-sha2-nistp256,ecdh-sha2-nistp384,ecdh-sha2-nistp521,diffie-hellman-group-exchange-sha256,diffie-hellman-group14-sha256,diffie-hellman-group16-sha512,diffie-hellman-group18-sha512,diffie-hellman-group-exchange-sha1,diffie-hellman-group14-sha1 PubkeyAcceptedAlgorithms ecdsa-sha2-nistp256,ecdsa-sha2-nistp256-cert-v01@openssh.com,sk-ecdsa-sha2-nistp256@openssh.com,sk-ecdsa-sha2-nistp256-cert-v01@openssh.com,ecdsa-sha2-nistp384,ecdsa-sha2-nistp384-cert-v01@openssh.com,ecdsa-sha2-nistp521,ecdsa-sha2-nistp521-cert-v01@openssh.com,ssh-ed25519,ssh-ed25519-cert-v01@openssh.com,sk-ssh-ed25519@openssh.com,sk-ssh-ed25519-cert-v01@openssh.com,rsa-sha2-256,rsa-sha2-256-cert-v01@openssh.com,rsa-sha2-512,rsa-sha2-512-cert-v01@openssh.com,ssh-rsa,ssh-rsa-cert-v01@openssh.com CASignatureAlgorithms ecdsa-sha2-nistp256,sk-ecdsa-sha2-nistp256@openssh.com,ecdsa-sha2-nistp384,ecdsa-sha2-nistp521,ssh-ed25519,sk-ssh-ed25519@openssh.com,rsa-sha2-256,rsa-sha2-512 RequiredRSASize 2048
[centos-admin@CENTOS-9 ~]$ update-crypto-policies --show
DEFAULT
Resolution
To resolve this issue, add ssh-rsa to the openssh configuration file:
-
Set the
crypto-policiesto legacy mode.[centos-admin@CENTOS-9 ~]$ update-crypto-policies --set LEGACY -
Check
openssh.config(ensure thatssh-rsais added).[centos-admin@CENTOS-9 ~]$ cat /etc/crypto-policies/back-ends/openssh.config Ciphers aes256-gcm@openssh.com,chacha20-poly1305@openssh.com,aes256-ctr,aes256-cbc,aes128-gcm@openssh.com,aes128-ctr,aes128-cbc MACs hmac-sha2-256-etm@openssh.com,hmac-sha1-etm@openssh.com,umac-128-etm@openssh.com,hmac-sha2-512-etm@openssh.com,hmac-sha2-256,hmac-sha1,umac-128@openssh.com,hmac-sha2-512 GSSAPIKexAlgorithms gss-curve25519-sha256-,gss-nistp256-sha256-,gss-group14-sha256-,gss-group16-sha512-,gss-gex-sha1-,gss-group14-sha1- KexAlgorithms curve25519-sha256,curve25519-sha256@libssh.org,ecdh-sha2-nistp256,ecdh-sha2-nistp384,ecdh-sha2-nistp521,diffie-hellman-group-exchange-sha256,diffie-hellman-group14-sha256,diffie-hellman-group16-sha512,diffie-hellman-group18-sha512,diffie-hellman-group-exchange-sha1,diffie-hellman-group14-sha1 PubkeyAcceptedAlgorithms ecdsa-sha2-nistp256,ecdsa-sha2-nistp256-cert-v01@openssh.com,sk-ecdsa-sha2-nistp256@openssh.com,sk-ecdsa-sha2-nistp256-cert-v01@openssh.com,ecdsa-sha2-nistp384,ecdsa-sha2-nistp384-cert-v01@openssh.com,ecdsa-sha2-nistp521,ecdsa-sha2-nistp521-cert-v01@openssh.com,ssh-ed25519,ssh-ed25519-cert-v01@openssh.com,sk-ssh-ed25519@openssh.com,sk-ssh-ed25519-cert-v01@openssh.com,rsa-sha2-256,rsa-sha2-256-cert-v01@openssh.com,rsa-sha2-512,rsa-sha2-512-cert-v01@openssh.com,ssh-rsa,ssh-rsa-cert-v01@openssh.com CASignatureAlgorithms ecdsa-sha2-nistp256,sk-ecdsa-sha2-nistp256@openssh.com,ecdsa-sha2-nistp384,ecdsa-sha2-nistp521,ssh-ed25519,sk-ssh-ed25519@openssh.com,rsa-sha2-256,rsa-sha2-512,ssh-rsa RequiredRSASize 2048 -
Retry the backup configuration in SDDC Manager.
Affected Products
VMWare Cloud on Dell EMC VxRail E560F, VMWare Cloud on Dell EMC VxRail E560N, VxRail E560 VCF, VxRail E560F VCF, VxRail E560N VCF, VxRail G560 VCF, VxRail G560F VCF, VxRail P570 VCF, VxRail P570F VCF, VxRail P580N VCF, VxRail S570 VCF
, VxRail V570 VCF, VxRail V570F VCF
...
Article Properties
Article Number: 000209752
Article Type: Solution
Last Modified: 17 Jul 2025
Version: 4
Find answers to your questions from other Dell users
Support Services
Check if your device is covered by Support Services.