Oracle RAC High Cluster Wait

This is second time i get cluster wait in newly installed oracle 11.2.0.4 two node RAC environment. I have found workaround for this issue as:

Environment:

OS: Oracle EL 6.9
DB: 2 Node Oracle Enterprise DB 11.2.0.4
Storage: ASM

Workaround:

check MTU for loopback device as
[oracle@trakyatipdbnode1 ~]$ ifconfig lo
lo        Link encap:Local Loopback
          inet addr:127.0.0.1  Mask:255.0.0.0
          inet6 addr: ::1/128 Scope:Host
          UP LOOPBACK RUNNING  MTU:65536  Metric:1
          RX packets:31675708 errors:0 dropped:0 overruns:0 frame:0
          TX packets:31675708 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:0
          RX bytes:41216739380 (38.3 GiB)  TX bytes:41216739380 (38.3 GiB)

Notice that MTU is 65k

To change MTU edit ifcfg-lo and add MTU=16436  for both nodes:

# vi /etc/sysconfig/network-scripts/ifcfg-lo

DEVICE=lo
IPADDR=127.0.0.1
NETMASK=255.0.0.0
NETWORK=127.0.0.0
# If you're having problems with gated making 127.0.0.0/8 a martian,
# you can change this to something else (255.255.255.255, for example)
BROADCAST=127.255.255.255
ONBOOT=yes
NAME=loopback
MTU=16436

After rebooting nodes one by one, you will get:

[oracle@trakyatipdbnode2 ~]$ ifconfig lo
lo        Link encap:Local Loopback
          inet addr:127.0.0.1  Mask:255.0.0.0
          inet6 addr: ::1/128 Scope:Host
          UP LOOPBACK RUNNING  MTU:16436  Metric:1
          RX packets:142 errors:0 dropped:0 overruns:0 frame:0
          TX packets:142 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:0
          RX bytes:13985 (13.6 KiB)  TX bytes:13985 (13.6 KiB)