This article explains the meaning of the "openpam_dispatch(): all modules were unsuccessful for pam_sm_authenticate()" syslog messages that are seen on devices that run Junos OS.
Junos RE logs
Oct 31 18:21:38.000 rshd[70818]: rshd: %DAEMON-3: in openpam_dispatch(): all modules were unsuccessful for pam_sm_authenticate() Oct 31 18:21:47.000 rshd[21877]: rshd: %DAEMON-3: in openpam_dispatch(): all modules were unsuccessful for pam_sm_authenticate() Oct 31 18:21:51.000 rshd[70819]: rshd: %DAEMON-3: in openpam_dispatch(): all modules were unsuccessful for pam_sm_authenticate() Oct 31 18:21:51.000 rshd[33761]: rshd: %DAEMON-3: in openpam_dispatch(): all modules were unsuccessful for pam_sm_authenticate() Oct 31 18:21:52.000 rshd[70821]: rshd: %DAEMON-3: in openpam_dispatch(): all modules were unsuccessful for pam_sm_authenticate() Oct 31 18:21:52.000 rshd[25703]: rshd: %DAEMON-3: in openpam_dispatch(): all modules were unsuccessful for pam_sm_authenticate() Oct 31 18:21:53.000 rshd[70822]: rshd: %DAEMON-3: in openpam_dispatch(): all modules were unsuccessful for pam_sm_authenticate() Oct 31 18:22:02.000 rshd[21880]: rshd: %DAEMON-3: in openpam_dispatch(): all modules were unsuccessful for pam_sm_authenticate() Oct 31 18:22:06.000 rshd[70823]: rshd: %DAEMON-3: in openpam_dispatch(): all modules were unsuccessful for pam_sm_authenticate()
It is expected to see such logs. The logs indicate that the remote shell (rshd) and remote copy (rcp) operations are not happening successfully due to a version mismatch between the Routing Engines (REs) that are installed and running. These logs "in openpam_dispatch(): all modules were unsuccessful for pam_sm_authenticate()" are internal to the Routing Engine on the device and are typically caused by unsuccessful RSH/ RDP/ TNP connection attempts from the backup RE to the primary on the management interface (em0/fxp0/me0). These messages usually appear when different OS versions are running on the primary and backup RE.
In case the errors are seen on single RE devices, it could be due to some transient issues with interaction with these commands. Ideally, such issues may be seen on single RE devices after an upgrade.
The remote shell (rsh) is a command-line computer program that can execute shell commands as another user, and on another computer across a computer network. The remote system to which rsh connects runs the rsh daemon (rshd). rsh executes commands on the host. rsh copies its standard input to the remote command, the standard output of the remote command to its standard output, and the standard error of the remote command to its standard error. Interrupt, quit, and terminate signals are propagated to the remote command; rsh normally terminates when the remote command does.
The remote copy (rcp) is a command-line computer program that copies files to or from a remote computer or between two remote computers. The command is similar to cp, except that the remote computer and possibly the username on the remote computer both need to be prefixed to the file name.
Remote Desktop Protocol (rdp) is a proprietary protocol that provides a user with a graphical interface to connect to another computer over a network connection. Users employ the RDP client software for this purpose, while the other computer must run the RDP server software. rdp servers take the request from various client operating systems.
To troubleshoot and resolve the error, perform the following:
Verify the Junos OS version on the primary/backup RE:
user@host> show version invoke-on all-routing-engines re0: -------------------------------------------------------------------------- Hostname: XXX Model: mx480 Junos: 17.3R3.9 <snip> re1: -------------------------------------------------------------------------- Hostname: XXX Model: mx480 Junos: 13.3R9.13 >>>> Version mismatch
To resolve the error, consider a reboot or power cycle of the RE.
Note: This will take the device down and needs to be performed in a Maintenance Window.
If the error persists after reboot, contact Support .