A few words about some important changes in upstream stable:

1. Some of the configuration file syntax has changed, but existing configurations should still work. A few configuration parameters have been deprecated, but this should only cause a warning at runtime.

2. VRRPv3 was introduced in keepalived since 1.2.13 (current version in RHEL). This is not compatible with VRRPv2, but it must been explicitly enabled in the configuration. The default is still VRRPv2. Important point is that nodes running in VRRPv3 will not work in conjunctions with nodes running VRRPv2, so customers that wish to upgrade and run VRRPv3 will not be able to to rolling upgrades.

3. There are on on-wire changes for VRRPv2, so existing deployments (version 1.2.13) should work with the new version (1.3.2). Rolling upgrades should work. Note that I've done some testing already and have no run into any problems.

4. The OpenStack Neutron team must test this with L3-HA agent to insure no breakage.

+1 for upgrading.
I have spent a little time time trying to figure out why the 'nopreempt' config option doesn't work. It seems that it is broken in the current (1.2.13) version. It is fixed in 1.2.14, but rather than request it is backported a jump to the latest release would be good.

Here is a documented case of Keepalived 1.2.15 and older causing issues for high availability with OpenStack's Neutron service: [ https://bugs.launchpad.net/neutron/+bug/1497272 ]. We have resorted to building our own RPM for 1.2.16 to overcome these issues. It would be ideal to have the official Red Hat RPMs updated. 

We have tried compiling the latest 1.2.X branch (currently 1.2.24) but it complained about missing functionality from the SNMP library so that may also need to be updated as well. For reference, here's the exact error we get while building 1.2.24.

===============
./configure --build=x86_64-redhat-linux-gnu --host=x86_64-redhat-linux-gnu --program-prefix= --disable-dependency-tracking --prefix=/usr --exec-prefix=/usr --bindir=/usr/bin --sbindir=/usr/sbin --sysconfdir=/etc --datadir=/usr/share --includedir=/usr/include --libdir=/usr/lib64 --libexecdir=/usr/libexec --localstatedir=/var --sharedstatedir=/var/lib --mandir=/usr/share/man --infodir=/usr/share/info --enable-snmp --enable-sha1
<OMITTED>
checking for net-snmp-config... /usr/bin/net-snmp-config
checking whether C compiler supports flag "-DNETSNMP_ENABLE_IPV6 -fno-strict-aliasing -O2 -g -pipe -Wall -Wp,-D_FORTIFY_SOURCE=2 -fexceptions -fstack-protector-strong --param=ssp-buffer-size=4 -grecord-gcc-switches -m64 -mtune=generic -D_RPM_4_4_COMPAT -Ulinux -Dlinux=linux -D_REENTRANT -D_GNU_SOURCE -fno-strict-aliasing -pipe -fstack-protector -I/usr/local/include -D_LARGEFILE_SOURCE -D_FILE_OFFSET_BITS=64 -I/usr/lib64/perl5/CORE -I/usr/include -DNETSNMP_NO_INLINE -L/usr/lib64 -lnetsnmpmibs -lnetsnmpagent -lnetsnmp -Wl,-z,relro -Wl,-z,now -lssl -lssl -lcrypto -lm -Wl,--enable-new-dtags -Wl,-rpath,/usr/lib64/perl5/CORE" from Net-SNMP... yes
checking for netsnmp_enable_subagent... no
configure: error: *** no subagent support in net-snmp
===============

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, 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/RHBA-2017:2169