With OpenSSH 9.9p1 (VRMF 9.9.3015.1000), the process table will show the sshd daemon in the following fashion:
sshd: /usr/sbin/sshd -D [listener] 0 of 10-100 startups
As stated by the OpenSSH community, OpenSSH 9.9p1 (9.9.3015.1000) has the following design changes:
1. Listener binary (sshd).
2. Per-session binary (sshd-session).
When sshd server is in the listening state, only the listener binary shows up in the process table, as follows:
root 5636544 4522392 0 17:19:14 - 0:00 sshd: /usr/sbin/sshd -D [listener] 0 of 10-100 startups
Some of the key design changes are:
1. The sshd listener binary starts up with the -D flag, enabling the debug level logging by default, compared to earlier versions, which defaulted to the INFO syslog facility.
2. When no clients are connected, only the sshd binary is started, as shown above. The whole purpose of the sshd binary in the new design is to be on the standby mode, in case of any incoming ssh connections.
3. When a client connects to the sshd server, the on-demand sshd-session binary is started.
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Carlo Castillo
Client Services Manager
IBM Redbooks Gold Author
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