On proxy
Message size 70934946 from x.x.x.x exceeds the maximum size 67108864 bytes. Message ignored
On server
Feb 6 11:01:29 xxxxx Zabbix server[24062]: sending configuration data to proxy "....proxy1.....", datalen 70934946
Feb 6 11:01:29 xxxxx Zabbix server[24062]: cannot send configuration: ZBX_TCP_WRITE() failed: [32] Broken pipe
Found that ZBX_MAX_RECV_DATA_SIZE changed
zabbix-2.0.9/include/common.h:#define ZBX_MAX_RECV_DATA_SIZE (128 * ZBX_MEBIBYTE)
zabbix-2.2.1/include/common.h:#define ZBX_MAX_RECV_DATA_SIZE (64 * ZBX_MEBIBYTE)
Circumvented by changing the value and recompiling a local proxy module.