Setting blocker- as this appears to be a configuration issue.  

The "default user 'keepalived_script' for script execution does not exist" message is only a warning.  According to <https://www.keepalived.org/manpage.html>, keepalived defaults to the user "keepalived_script" if it exists and otherwise defaults to the user that keepalived is already running as.  The reason why keepalived exits is probably because the "enp0s3" interface doesn't exist.  Does the host have an "enp0s3" interface?  If not, try setting OPENSHIFT_HA_NETWORK_INTERFACE in the ipfailover deployment to the correct interface name.

melvinjoseph@mjoseph-mac Downloads % oc set env deploy/ipfailover OPENSHIFT_HA_NETWORK_INTERFACE=ens3
deployment.apps/ipfailover updated
melvinjoseph@mjoseph-mac Downloads % oc get po                                                       
NAME                          READY   STATUS    RESTARTS   AGE
ipfailover-796d85684d-6dlb4   1/1     Running   0          20s
ipfailover-796d85684d-7dtx2   1/1     Running   0          20s

When i changed the interface to ens3 in the ipfailover config file the pods came up. 
Normally when i use this deploy script there was not such issue in past, and i was verifying one ipfailvoer bug, so thought the fix break the feature.

The naming difference is related to the underlying hardware.  The naming system that systemd/udev uses to name network interfaces is defined at <https://www.freedesktop.org/wiki/Software/systemd/PredictableNetworkInterfaceNames/>:

> The following different naming schemes for network interfaces are now supported by udev natively:
> 
> 1. Names incorporating Firmware/BIOS provided index numbers for on-board devices (example: eno1)
> 2. Names incorporating Firmware/BIOS provided PCI Express hotplug slot index numbers (example: ens1)
> 3. Names incorporating physical/geographical location of the connector of the hardware (example: enp2s0)
> 4. Names incorporating the interfaces's MAC address (example: enx78e7d1ea46da)
> 5. Classic, unpredictable kernel-native ethX naming (example: eth0)

So apparently previous clusters on which you have tested keepalived-ipfailover used scheme 3 (resulting in the name "enp0s3"), but for more recent tests, you have a cluster with PCIe hotplug slots, which are named using scheme 2 (resulting in the name "ens3").  

The keepalived-ipfailover configuration script guesses a few names if the user doesn't configure one:

> VBOX_INTERFACES="enp0s3 enp0s8 eth1"

Source: <https://github.com/openshift/images/blob/86494446733fc171ee757e8166191e32d5931eb9/ipfailover/keepalived/lib/utils.sh#L6>.

> function get_network_device() {
>   for dev in $1 ${VBOX_INTERFACES}; do
>     if ip addr show dev "$dev" &> /dev/null; then
>       echo "$dev"
>       return
>     fi
>   done
> 
>   ip route get 8.8.8.8 | awk '/dev/ { f=NR }; f && (NR-1 == f)' RS=" "
> }

Source: <https://github.com/openshift/images/blob/86494446733fc171ee757e8166191e32d5931eb9/ipfailover/keepalived/lib/utils.sh#L246-L255>.

We could add "ens3" to the end of VBOX_INTERFACES to autodetect this name as well.  Is that desirable?

melvinjoseph@mjoseph-mac Downloads % oc get clusterversion
NAME      VERSION                                                   AVAILABLE   PROGRESSING   SINCE   STATUS
version   4.10.0-0.ci.test-2022-03-12-022506-ci-ln-rttk652-latest   True        False         70m     Cluster version is 4.10.0-0.ci.test-2022-03-12-022506-ci-ln-rttk652-latest
melvinjoseph@mjoseph-mac Downloads % oc create sa ipfailover
serviceaccount/ipfailover created
melvinjoseph@mjoseph-mac Downloads % oc adm policy add-scc-to-user priviledged -z ipfailover
clusterrole.rbac.authorization.k8s.io/system:openshift:scc:priviledged added: "ipfailover"
melvinjoseph@mjoseph-mac Downloads % oc adm policy add-scc-to-user hostnetwork -z ipfailover
clusterrole.rbac.authorization.k8s.io/system:openshift:scc:hostnetwork added: "ipfailover"
melvinjoseph@mjoseph-mac Downloads % oc create configmap keepalived-checkscript --from-file=mycheckscript.sh
configmap/keepalived-checkscript createdmelvinjoseph@mjoseph-mac Downloads % oc create -f  https://github.com/jechen0648/ipfailover/blob/main/deploy-ipfailover.yaml
deployment.apps/ipfailover created
melvinjoseph@mjoseph-mac Downloads %  oc get all -owide
NAME                              READY   STATUS    RESTARTS   AGE   IP           NODE                                 NOMINATED NODE   READINESS GATES
pod/ipfailover-788b595477-cd672   1/1     Running   0          18s   10.0.3.139   rttk652-b5564-vnk62-worker-0-t4v78   <none>           <none>
pod/ipfailover-788b595477-xblc5   1/1     Running   0          18s   10.0.1.135   rttk652-b5564-vnk62-worker-0-m77tv   <none>           <none>

NAME                 TYPE           CLUSTER-IP   EXTERNAL-IP                            PORT(S)   AGE   SELECTOR
service/kubernetes   ClusterIP      172.30.0.1   <none>                                 443/TCP   93m   <none>
service/openshift    ExternalName   <none>       kubernetes.default.svc.cluster.local   <none>    89m   <none>

NAME                         READY   UP-TO-DATE   AVAILABLE   AGE   CONTAINERS              IMAGES                                                                                                                   SELECTOR
deployment.apps/ipfailover   2/2     2            2           20s   ipfailover-keepalived   quay.io/openshift-release-dev/ocp-v4.0-art-dev@sha256:644bf2d63cc24035ec82a39e0b14e6d61e3ca4ba39181b409590132f59bfc2cf   ipfailover=ipfailover

NAME                                    DESIRED   CURRENT   READY   AGE   CONTAINERS              IMAGES                                                                                                                   SELECTOR
replicaset.apps/ipfailover-788b595477   2         2         2       19s   ipfailover-keepalived   quay.io/openshift-release-dev/ocp-v4.0-art-dev@sha256:644bf2d63cc24035ec82a39e0b14e6d61e3ca4ba39181b409590132f59bfc2cf   ipfailover=ipfailover,pod-template-hash=788b595477
melvinjoseph@mjoseph-mac Downloads % oc logs ipfailover-788b595477-cd672
  - Loading ip_vs module ...
  - Checking if ip_vs module is available ...
ip_vs                 172032  0
  - Module ip_vs is loaded.
  - check for iptables rule for keepalived multicast (224.0.0.18) ...
chroot: cannot change root directory to '/host': No such file or directory
  - adding iptables rule to INPUT to access 224.0.0.18.
chroot: cannot change root directory to '/host': No such file or directory
  - Generating and writing config to /etc/keepalived/keepalived.conf
  - Starting failover services ...
Sat Mar 12 04:25:56 2022: Starting Keepalived v2.1.5 (07/13,2020)
Sat Mar 12 04:25:56 2022: Running on Linux 4.18.0-305.40.2.el8_4.x86_64 #1 SMP Tue Mar 8 14:29:54 EST 2022 (built for Linux 4.18.0)
Sat Mar 12 04:25:56 2022: Command line: '/usr/sbin/keepalived' '-D' '-n' '--log-console'
Sat Mar 12 04:25:56 2022: Opening file '/etc/keepalived/keepalived.conf'.
Sat Mar 12 04:25:56 2022: NOTICE: setting config option max_auto_priority should result in better keepalived performance
Sat Mar 12 04:25:56 2022: Starting VRRP child process, pid=74
Sat Mar 12 04:25:56 2022: Registering Kernel netlink reflector
Sat Mar 12 04:25:56 2022: Registering Kernel netlink command channel
Sat Mar 12 04:25:56 2022: Opening file '/etc/keepalived/keepalived.conf'.
Sat Mar 12 04:25:56 2022: WARNING - default user 'keepalived_script' for script execution does not exist - please create.
Sat Mar 12 04:25:56 2022: (/etc/keepalived/keepalived.conf: Line 29) Truncating auth_pass to 8 characters
Sat Mar 12 04:25:56 2022: SECURITY VIOLATION - scripts are being executed but script_security not enabled.
Sat Mar 12 04:25:56 2022: (ipfailover_VIP_1) Warning - nopreempt will not work with initial state MASTER - clearing
Sat Mar 12 04:25:56 2022: Assigned address 10.0.3.139 for interface ens3
Sat Mar 12 04:25:56 2022: Assigned address fe80::f7c0:638d:a465:aba7 for interface ens3
Sat Mar 12 04:25:56 2022: Registering gratuitous ARP shared channel
Sat Mar 12 04:25:56 2022: (ipfailover_VIP_1) removing VIPs.
Sat Mar 12 04:25:56 2022: VRRP sockpool: [ifindex(  2), family(IPv4), proto(112), fd(10,11)]
Sat Mar 12 04:25:56 2022: Script `chk_ipfailover` now returning 1
Sat Mar 12 04:25:56 2022: VRRP_Script(chk_ipfailover) failed (exited with status 1)
Sat Mar 12 04:25:56 2022: (ipfailover_VIP_1) Entering FAULT STATE

Since the problem described in this bug report should be
resolved in a recent advisory, it has been closed with a
resolution of ERRATA.

For information on the advisory (Important: OpenShift Container Platform 4.11.0 bug fix and security update), and where to find the updated
files, follow the link below.

If the solution does not work for you, open a new bug report.

https://access.redhat.com/errata/RHSA-2022:5069