Description of problem:
After UC FFU to 16.2.0 tripleo service tripleo_memcached_healthcheck.service fails with error: "healthcheck_memcached[132238]: /usr/share/openstack-tripleo-common/healthcheck/common.sh: line 160: $1: unbound variable" [1].

Looking at code inside /usr/share/openstack-tripleo-common/healthcheck/memcached it calls wrap_ipv6 function against /etc/sysconfig/memcached file:

 [root@undercloud sysconfig]# cat /usr/share/openstack-tripleo-common/healthcheck/memcached 
#!/bin/bash
. ${HEALTHCHECK_SCRIPTS:-/usr/share/openstack-tripleo-common/healthcheck}/common.sh

listen_addr=$(wrap_ipv6 $(awk 'match($0, /-l +([0-9a-fA-F\.\:]+) /, a) {print a[1]}' /etc/sysconfig/memcached))

echo "version" | socat - TCP:$listen_addr:11211 1>/dev/null
exit $?

but running that awk returns null / empty string:

 [root@undercloud ~]# awk 'match($0, /-l +([0-9a-fA-F\.\:]+) /, a) {print a[1]}' /var/lib/config-data/puppet-generated/memcached/etc/sysconfig/memcached 
 [root@undercloud ~]# cat /var/lib/config-data/puppet-generated/memcached/etc/sysconfig/memcached 
PORT="11211"
USER="memcached"
MAXCONN="8192"
CACHESIZE="15979"
OPTIONS="-v -l 127.0.0.1,192.168.201.30 -U 0 -X -t 4"

instead on the old one returns the loopback address:

 [root@undercloud ~]# cat /etc/sysconfig/memcached.rpmsave 
PORT="11211"
USER="memcached"
MAXCONN="8192"
CACHESIZE="11975"
OPTIONS="-v -l 127.0.0.1 -U 0 -X -t 4 >> /var/log/memcached.log 2>&1"

IMO the awk could be fixed inserting "\s*":

 [root@undercloud ~]# awk 'match($0, /-l +([0-9a-fA-F\.\:]+)\s*/, a) {print a[1]}' /var/lib/config-data/puppet-generated/memcached/etc/sysconfig/memcached 
127.0.0.1

 [root@undercloud healthcheck]# diff -u /usr/share/openstack-tripleo-common/healthcheck/memcached.ORIG /usr/share/openstack-tripleo-common/healthcheck/memcached
--- /usr/share/openstack-tripleo-common/healthcheck/memcached.ORIG      2021-05-15 12:48:09.000000000 +0000
+++ /usr/share/openstack-tripleo-common/healthcheck/memcached   2021-12-02 10:52:53.925922152 +0000
@@ -1,7 +1,7 @@
 #!/bin/bash
 . ${HEALTHCHECK_SCRIPTS:-/usr/share/openstack-tripleo-common/healthcheck}/common.sh
 
-listen_addr=$(wrap_ipv6 $(awk 'match($0, /-l +([0-9a-fA-F\.\:]+) /, a) {print a[1]}' /etc/sysconfig/memcached))
+listen_addr=$(wrap_ipv6 $(awk 'match($0, /-l +([0-9a-fA-F\.\:]+)\s*/, a) {print a[1]}' /etc/sysconfig/memcached))
 
 echo "version" | socat - TCP:$listen_addr:11211 1>/dev/null
 exit $?


[1] 
 [root@undercloud sysconfig]# systemctl status tripleo_memcached_healthcheck.service
● tripleo_memcached_healthcheck.service - memcached healthcheck
   Loaded: loaded (/etc/systemd/system/tripleo_memcached_healthcheck.service; disabled; vendor preset: disabled)
   Active: failed (Result: exit-code) since Thu 2021-12-02 10:35:17 UTC; 2s ago
  Process: 153371 ExecStart=/usr/bin/podman exec --user root memcached /openstack/healthcheck (code=exited, status=1/FAILURE)
 Main PID: 153371 (code=exited, status=1/FAILURE)

Dec 02 10:35:16 undercloud.example.com systemd[1]: Starting memcached healthcheck...
Dec 02 10:35:17 undercloud.example.com podman[153371]: 2021-12-02 10:35:17.365222614 +0000 UTC m=+0.523695166 container exec 2c1b6d0fff654efbbeaa6d4797225830997f0886108796e9514036b33443f24f (image=undercloud.ctlplane.example.com:8787/r>
Dec 02 10:35:17 undercloud.example.com healthcheck_memcached[153371]: /usr/share/openstack-tripleo-common/healthcheck/common.sh: line 160: $1: unbound variable
Dec 02 10:35:17 undercloud.example.com systemd[1]: tripleo_memcached_healthcheck.service: Main process exited, code=exited, status=1/FAILURE
Dec 02 10:35:17 undercloud.example.com systemd[1]: tripleo_memcached_healthcheck.service: Failed with result 'exit-code'.
Dec 02 10:35:17 undercloud.example.com systemd[1]: Failed to start memcached healthcheck.

Version-Release number of selected component (if applicable):


How reproducible:


Steps to Reproduce:
1. UC FFU from 13 to 16.2.0
2. systemctl status tripleo_memcached_healthcheck.service
3.

Actual results:
Service tripleo_memcached_healthcheck.service fails with error:
healthcheck_memcached[201289]: /usr/share/openstack-tripleo-common/healthcheck/common.sh: line 160: $1: unbound variable


Expected results:
Service tripleo_memcached_healthcheck.service able to check memcached status


Additional info: