[Starlingx-discuss] pmond and systemd handling for fm-rest-api

[Cordoba Malibran, Erich]

Hi,

I'm converting the fm-api init script to be handled completely by
systemd, however I'm seeing that, once I created the unit file, pmod is
constantly launching fm-api (which causes a failure in fm-api is there
is a conflict in the network address usage).

So, this is my unit file for fm-api.

[Unit]
Description=Fault Management REST API Service
After=nfscommon.service sw-patch.service
After=network-online.target systemd-udev-settle.service

[Service]
Type=simple
RemainAfterExit=yes
User=root
ExecStart=/usr/bin/fm-api --config-file=/etc/fm/fm.conf
PIDFile=/var/run/fm-api.pid

[Install]
WantedBy=multi-user.target


Then I edit the /etc/pmon.d/fm-api.conf file to this:

[process]
process  = fm-api
pidfile  = /var/run/fm-api.pid
service  = fm-api.service
style    = systemd        ; ocf or lsb
severity = major          ; minor, major, critical
restarts = 3              ; restarts before error assertion
interval = 5              ; number of seconds to wait between restarts
debounce = 20             ; number of seconds to wait before degrade
clear


What I've seen is that pmond is looking for the pidfile, but this is
not created as this was done by the deleted init script[0].

Also, according to this comment[1], looking for the pidfile is the last
resource but I can see frequent attempts to find this file, see below: 

$ sudo strace -e trace=file -p 86386 

--- SIGRT_2 {si_signo=SIGRT_2, si_code=SI_TIMER, si_timerid=0x20, si_overrun=0, si_value={int=6882944, ptr=0x690680}} ---                                                                     
open("/var/run/fm-api.pid", O_RDONLY)   = -1 ENOENT (No such file or directory)                                                                                                               
--- SIGCHLD {si_signo=SIGCHLD, si_code=CLD_EXITED, si_pid=3222970, si_uid=0, si_status=0, si_utime=0, si_stime=0} ---
--- SIGCHLD {si_signo=SIGCHLD, si_code=CLD_EXITED, si_pid=3222617, si_uid=0, si_status=0, si_utime=0, si_stime=0} ---
--- SIGRT_2 {si_signo=SIGRT_2, si_code=SI_TIMER, si_timerid=0x20, si_overrun=0, si_value={int=6882944, ptr=0x690680}} ---
--- SIGRT_2 {si_signo=SIGRT_2, si_code=SI_TIMER, si_timerid=0x20, si_overrun=0, si_value={int=6882944, ptr=0x690680}} ---
--- SIGRT_2 {si_signo=SIGRT_2, si_code=SI_TIMER, si_timerid=0x7efa, si_overrun=0, si_value={int=6853136, ptr=0x689210}} ---
--- SIGRT_2 {si_signo=SIGRT_2, si_code=SI_TIMER, si_timerid=0x20, si_overrun=0, si_value={int=6882944, ptr=0x690680}} ---
open("/var/run/fm-api.pid", O_RDONLY)   = -1 ENOENT (No such file or directory)
--- SIGRT_2 {si_signo=SIGRT_2, si_code=SI_TIMER, si_timerid=0x7ed1, si_overrun=0, si_value={int=6883584, ptr=0x690900}} ---


Does anybody know what can be causing this behavior ? 

Thanks


-Erich


- [0] https://opendev.org/starlingx/fault/src/branch/master/fm-rest-api/fm/scripts/fm-api#L29
- [1] https://opendev.org/starlingx/metal/src/branch/master/mtce/src/pmon/pmonHdlr.cpp#L1621