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-rw-r--r--sshd_config.546
1 files changed, 45 insertions, 1 deletions
diff --git a/sshd_config.5 b/sshd_config.5
index a3357d445..15bd8d988 100644
--- a/sshd_config.5
+++ b/sshd_config.5
@@ -58,6 +58,33 @@ Arguments may optionally be enclosed in double quotes
58.Pq \&" 58.Pq \&"
59in order to represent arguments containing spaces. 59in order to represent arguments containing spaces.
60.Pp 60.Pp
61Note that the Debian
62.Ic openssh-server
63package sets several options as standard in
64.Pa /etc/ssh/sshd_config
65which are not the default in
66.Xr sshd 8 .
67The exact list depends on whether the package was installed fresh or
68upgraded from various possible previous versions, but includes at least the
69following:
70.Pp
71.Bl -bullet -offset indent -compact
72.It
73.Cm Protocol No 2
74.It
75.Cm ChallengeResponseAuthentication No no
76.It
77.Cm X11Forwarding No yes
78.It
79.Cm PrintMotd No no
80.It
81.Cm AcceptEnv No LANG LC_*
82.It
83.Cm Subsystem No sftp /usr/lib/openssh/sftp-server
84.It
85.Cm UsePAM No yes
86.El
87.Pp
61The possible 88The possible
62keywords and their meanings are as follows (note that 89keywords and their meanings are as follows (note that
63keywords are case-insensitive and arguments are case-sensitive): 90keywords are case-insensitive and arguments are case-sensitive):
@@ -562,7 +589,7 @@ The default is 120 seconds.
562Gives the verbosity level that is used when logging messages from 589Gives the verbosity level that is used when logging messages from
563.Xr sshd 8 . 590.Xr sshd 8 .
564The possible values are: 591The possible values are:
565QUIET, FATAL, ERROR, INFO, VERBOSE, DEBUG, DEBUG1, DEBUG2, and DEBUG3. 592SILENT, QUIET, FATAL, ERROR, INFO, VERBOSE, DEBUG, DEBUG1, DEBUG2, and DEBUG3.
566The default is INFO. 593The default is INFO.
567DEBUG and DEBUG1 are equivalent. 594DEBUG and DEBUG1 are equivalent.
568DEBUG2 and DEBUG3 each specify higher levels of debugging output. 595DEBUG2 and DEBUG3 each specify higher levels of debugging output.
@@ -680,6 +707,20 @@ are refused if the number of unauthenticated connections reaches
680Specifies whether password authentication is allowed. 707Specifies whether password authentication is allowed.
681The default is 708The default is
682.Dq yes . 709.Dq yes .
710.It Cm PermitBlacklistedKeys
711Specifies whether
712.Xr sshd 8
713should allow keys recorded in its blacklist of known-compromised keys (see
714.Xr ssh-vulnkey 1 ) .
715If
716.Dq yes ,
717then attempts to authenticate with compromised keys will be logged but
718accepted.
719If
720.Dq no ,
721then attempts to authenticate with compromised keys will be rejected.
722The default is
723.Dq no .
683.It Cm PermitEmptyPasswords 724.It Cm PermitEmptyPasswords
684When password authentication is allowed, it specifies whether the 725When password authentication is allowed, it specifies whether the
685server allows login to accounts with empty password strings. 726server allows login to accounts with empty password strings.
@@ -900,6 +941,9 @@ This avoids infinitely hanging sessions.
900.Pp 941.Pp
901To disable TCP keepalive messages, the value should be set to 942To disable TCP keepalive messages, the value should be set to
902.Dq no . 943.Dq no .
944.Pp
945This option was formerly called
946.Cm KeepAlive .
903.It Cm UseDNS 947.It Cm UseDNS
904Specifies whether 948Specifies whether
905.Xr sshd 8 949.Xr sshd 8