The pe_user is created by Space as local user to communicate with Policy Enforcer and the authentication should stay local between the two nodes
However sometimes Space sends authentication requests to the TACACS server were the pe_user does not exist as a valid user in Active Directory which causes ISE to generate thousand of auth failures hourly.
These log messages can be observed when this issue is happening.
Jan 23 01:42:38 localhost tac_plus[26924]: login failure: pe_user <ip address> (<ip address>) unknown-port
Jan 23 01:43:42 localhost tac_plus[26929]: connect from <ip address> [<ip address>]
Jan 23 01:43:42 localhost tac_plus[26929]: login failure: pe_user <ip address> (<ip address>) unknown-port
025-01-30 05:25:20,386 WARN [net.juniper.jmp.interceptors.security.SecurityInterceptor] (default task-668) invoking authenticateUser mehtod for request
2025-01-30 05:25:20,389 WARN [net.juniper.jmp.interceptors.security.SecurityInterceptor] (default task-668) authenticateLocalUser userName::pe_user remoteIpAddress::<ip address> reqPath::/api/space/device-management/devices
2025-01-30 05:25:20,413 WARN [net.juniper.jmp.interceptors.security.SecurityInterceptor] (default task-668) authenticateLocalUser making remoteAuth(Local) call for ::pe_user remoteIpAddress::<ip address> reqPath::/api/space/device-management/devices
2025-01-30 05:25:20,418 WARN [net.juniper.jmp.cmp.systemService.utilities.LoginUtilities] (default task-668) Validate user pe_user from client ip: <ip address> in Auth server ip: <ip address>
2025-01-30 05:25:20,425 WARN [net.juniper.jmp.cmp.systemService.utilities.LoginUtilities] (default task-668) validateRemoteUser status ACCESS_REJECT
2025-01-30 05:25:20,462 WARN [net.juniper.jmp.cmp.systemService.utilities.LoginUtilities] (default task-668) validatePasswordLocal status Login ID: pe_user, First Name: Policy, Last Name: Enforcer, Email: None,User Type: Local
This issue is resolved in Junos Space 23.1R1 HPv6
There is no workaround
The reported issue is resolved in the latest release, 24.1R4.
PR1860367