Algorithm negotiation failed for SSH Secure Shell Client

If you are using the dated SSH Secure Shell Client 3.2.9, you may have issue connect to the more updated OpenSSH Server.

SSH

If you cannot change the client (which is recommended), you will have to update the OpenSSH Server on Linux. Add this in

# vim /etc/ssh/sshd_config
# Ciphers
Ciphers aes128-cbc,aes192-cbc,aes256-cbc,blowfish-cbc,arcfour
KexAlgorithms diffie-hellman-group1-sha1

*If you are using Centrify-OpenSSH, you have to modify /etc/centrifydc/ssh/sshd_config and do the same

References:

  1. Bug 1228013 – Server responded “Algorithm negotiation failed”

Enable Centrify Agent to read UID and GID from Centrify DirectManage Access Manager

We purchased Centrify Standard and setup the DirectManage Access Manager. Next we proceed to install the client agent on the compute node.

After unpacking and installing the agent, when we do a

# getent passwd  |grep kittycool
kittycool:x:1304567321211:1304567321211:kittycool:/home/kittycool:/bin/bash
kittycool:x:10001:10001:kittycool:/home/kittycool:/bin/bash

Apparently, the getent passwd |grep kittycool is pulling both the Active Directory UID and the DirectManage Access and the user UID differs

To resolve this issue, you need to specify the zone which is used by DirectManage Access Manager, so your UID of the user will pick from the DirectManage Access Manager.

# adjoin -z cluster -u OU_Administrator  staff.mycompany.com.sg -c "staff.mycompany.com.sg/HPC/Computers"

To check it is displaying the correct UID and GID,

# getent passwd  |grep kittycool
kittycool:x:10001:10001:kittycool:/home/kittycool:/bin/bash