Configuring When To Re-Generate An Ssh Key; Configuring The Ssh Server Key Exchange Algorithm - Dell Z9000 Configuration Manual

Configuring When to Re-generate an SSH Key

You can configure the time-based or volume-based rekey threshold for an SSH session. If both threshold
types are configured, the session rekeys when either one of the thresholds is reached.
To configure the time or volume rekey threshold at which to re-generate the SSH key during an SSH
session, use the ip ssh rekey [time rekey-interval] [volume rekey-limit] command.
CONFIGURATION mode.
Configure the following parameters:
• rekey-interval: time-based rekey threshold for an SSH session. The range is from 10 to 1440 minutes.
The default is 60 minutes.
• rekey-limit: volume-based rekey threshold for an SSH session. The range is from 1 to 4096 to
megabytes. The default is 1024 megabytes.
Examples
The following example configures the time-based rekey threshold for an SSH session to 30 minutes.
Dell(conf)#ip ssh rekey time 30
The following example configures the volume-based rekey threshold for an SSH session to 4096
megabytes.
Dell(conf)#ip ssh rekey volume 4096

Configuring the SSH Server Key Exchange Algorithm

To configure the key exchange algorithm for the SSH server, use the ip ssh server kex key-
exchange-algorithm command in CONFIGURATION mode.
key-exchange-algorithm : Enter a space-delimited list of key exchange algorithms that will be used by
the SSH server.
The following key exchange algorithms are available:
• diffie-hellman-group-exchange-sha1
• diffie-hellman-group1-sha1
• diffie-hellman-group14-sha1
The default key exchange algorithms are the following:
• diffie-hellman-group-exchange-sha1
• diffie-hellman-group1-sha1
• diffie-hellman-group14-sha1
When FIPS is enabled, the default is diffie-hellman-group14-sha1.
Example of Configuring a Key Exchange Algorithm
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