By excluding SSH algorithms, you can restrict Site24x7 SSH Client from using the excluded algorithm while connecting to the SSH server during SFTP Transfer monitoring. Follow the steps mentioned below for SSH algorithm exclusion in On-Premise Poller during SFTP Transfer Monitoring:

Prerequisite:

Ensure that the On-Premise Poller is of version 4.6.9 or above.  If not, please update the On-Premise Poller to the latest version by navigating to Admin > On-Premise Poller and then hover over the hamburger icon on the right corner of the selected poller. Then click Upgrade and wait for a few mins for it to be upgraded.

1. Navigate to the On-Premise Poller installed directory in your system and then open the conf folder.
   

2. Right-click on the EUMServer.properties file and open it in any text editor. Use the below keys to disable the algorithms in the file. Be careful not to modify any existing keys in the EUMServer.properties file:               

1. ftp.exclude.kex.alg
   

2. ftp.exclude.ciphers
   

3. ftp.exclude.hamcs
   

4. ftp.exclude.public.key.alg
   

5. ftp.exclude.digest

For instance, to exclude "diffie-hellman-group-exchange-sha256" from KEX and "hmac-sha256" & "hmac-sha2-256-96" from HAMCs, change the value of the keys "ftp.exclude.kex.alg"and "ftp.exclude.hamcs" provide the keys as mentioned below: 
                     ftp.exclude.hamcs=hmac-sha256, hmac-sha2-256-96
                     ftp.exclude.kex.alg=diffie-hellman-group-exchange-sha256

# Provide a comma-seperated list of algorithms to be excluded.

#Supported Key Exchange Algorithm : diffie-hellman-group-exchange-sha256, diffie-hellman-group18-sha512, diffie-hellman-group17-sha512, diffie-hellman-group16-sha512, diffie-hellman-group15-sha512, diffie-hellman-group14-sha256, diffie-hellman-group-exchange-sha1, diffie-hellman-group14-sha1, ecdh-sha2-nistp256, ecdh-sha2-nistp384, ecdh-sha2-nistp521, diffie-hellman-group1-sha1

ftp.exclude.kex.alg=diffie-hellman-group-exchange-sha256, diffie-hellman-group-exchange-sha1, diffie-hellman-group14-sha256

#Supported Ciphers : ssh1-des, ssh1-3des, aes128-ctr, aes192-ctr, aes256-ctr, 3des-ctr, 3des-cbc, blowfish-cbc, aes128-cbc, aes192-cbc, aes256-cbc, arcfour, arcfour128, arcfour256, aes128-gcm@openssh.com, aes256-gcm@openssh.com

ftp.exclude.ciphers=aes192-ctr, aes256-ctr


#Supported HMAC : hmac-sha256, hmac-sha2-256-96, hmac-sha512, hmac-sha2-512-96, hmac-sha1, hmac-sha1-96, hmac-ripemd160, hmac-md5, hmac-md5-96


ftp.exclude.hamcs=hmac-sha256, hmac-sha2-256-96


#Supported Public Key : ssh-dss, ssh-rsa, x509v3-sign-rsa, x509v3-sign-dss, x509v3-sign-rsa-sha1, x509v3-ssh-rsa, x509v3-ssh-dss, x509v3-ecdsa-sha2-nistp256, x509v3-ecdsa-sha2-nistp384, x509v3-ecdsa-sha2-nistp521, ecdsa-sha2-nistp256, ecdsa-sha2-nistp384, ecdsa-sha2-nistp521, x509v3-rsa2048-sha256, ssh-rsa-cert-v01@openssh.com, ssh-dss-cert-v01@openssh.com, ecdsa-sha2-nistp256-cert-v01@openssh.com, ecdsa-sha2-nistp384-cert-v01@openssh.com, ecdsa-sha2-nistp521-cert-v01@openssh.com, ssh-ed25519

ftp.exclude.public.key.alg=x509v3-sign-rsa, x509v3-sign-dss

#Supported Digest : MD5, SHA-1, SHA1, SHA-256, SHA-384, SHA-512


ftp.exclude.digest=SHA1, SHA-256

      3. Restart the On-Premise Poller to get the changes updated.

 If the On-Premise Poller is upgraded soon after applying the above changes, the exclusion will get reverted. Please repeat the above process in this case.