Question

I have a rails application running on a server where I added some iptables rules to improve security. Now Omniauth callbacks stopped working. Every time I try to log in with any provider I get this error into my application log

Errno::ENETUNREACH (Network is unreachable - connect(2))

And this dropped package gets logged into syslog

IN=eth0 OUT= MAC=40:40:ea:31:ac:8d:64:00:f1:cd:1f:7f:08:00 SRC=66.220.147.99 DST=my_ip LEN=56 TOS=0x00 PREC=0x00 TTL=88 ID=0 DF PROTO=TCP SPT=443 DPT=37035 WINDOW=14480 RES=0x00 ACK SYN URGP=0

Can someone tell me what that entry in my syslog is about and what kind of iptables rule is needed to allow it.

If needed I could add also the rules I have applied this far.

EDIT:
The syslog line was incorrect, so I replaced it.

Answer 1

The answer to my original question found from http://lists.debian.org/debian-user/2002/07/msg01187.html

IN = interface the packet came in
OUT = interface used for sending the packet
MAC = MAC address for source and destination
SRC = IP of the sender
DST = IP of the receiver
LEN = Length of the packet
TOS = ?
PREC = Precedence
TTL = Time to live (hop count of the package)
ID = Packet ID number
DF = Don't fragment bit
PROTO = The protocol
SPT = Sender port
DPT = Receiving port
WINDOW = ?
RES = Received bits
And then some TCP flags in the end of the row. Didn't yet dig the meaning of those.
ACK = ?
SYN = ?
URGP = ?