Yesterday, the company’s server upgraded the hardware, only upgraded CPU and memory, and then after the restart, things running online will not run, check, all ports and services are open, firewall those, the results found that the ports and services, firewall allowed ports are open
Still can not run, to 10 o ‘clock in the evening, suddenly a friend said, or turn off the firewall to try, the result is good, forgot to check the firewall information
The only port we’ve used so far is

cat: /etc/sysconfig/iptables: Permission denied
[dev@chttl-8a6e210a8d27536a ~]$ sudo cat /etc/sysconfig/iptables
# Firewall configuration written by system-config-firewall
# Manual customization of this file is not recommended.
*filter
:INPUT ACCEPT [0:0]
:FORWARD ACCEPT [0:0]
:OUTPUT ACCEPT [0:0]
-A INPUT -m state --state ESTABLISHED,RELATED -j ACCEPT
-A INPUT -p icmp -j ACCEPT
-A INPUT -i lo -j ACCEPT
-A INPUT -m state --state NEW -m tcp -p tcp --dport 21 -j ACCEPT
-A INPUT -m state --state NEW -m tcp -p tcp --dport 22 -j ACCEPT-A INPUT -m state --state NEW -m tcp -p tcp --dport 25 -j ACCEPT
-A INPUT -m state --state NEW -m tcp -p tcp --dport 80 -j ACCEPT
-A INPUT -m state --state NEW -m tcp -p tcp --dport 3306 -j ACCEPT
-A INPUT -m state --state NEW -m tcp -p tcp --dport 27017 -j ACCEPT
-A INPUT -j REJECT --reject-with icmp-host-prohibited
-A FORWARD -j REJECT --reject-with icmp-host-prohibited

And that’s all,
The results after checking the firewall information found that TM also used SMB this I really do not understand

ack)
Jul 17 09:08:32 chttl-8a6e210a8d27536a smbd[1567]:   failed to retrieve printer list: NT_STATUS_UNSUCCESSFUL
Jul 17 09:21:32 chttl-8a6e210a8d27536a smbd[28014]: [2015/07/17 09:21:32.803089,  0] printing/print_cups.c:151(cups_connect)
Jul 17 09:21:32 chttl-8a6e210a8d27536a smbd[28014]:   Unable to connect to CUPS server localhost:631 - Connection refused
Jul 17 09:21:32 chttl-8a6e210a8d27536a smbd[1567]: [2015/07/17 09:21:32.803424,  0] printing/print_cups.c:528(cups_async_callback)
Jul 17 09:21:32 chttl-8a6e210a8d27536a smbd[1567]:   failed to retrieve printer list: NT_STATUS_UNSUCCESSFUL
Jul 17 09:34:33 chttl-8a6e210a8d27536a smbd[31824]: [2015/07/17 09:34:33.385856,  0] printing/print_cups.c:151(cups_connect)
Jul 17 09:34:33 chttl-8a6e210a8d27536a smbd[31824]:   Unable to connect to CUPS server localhost:631 - Connection refused
Jul 17 09:34:33 chttl-8a6e210a8d27536a smbd[1567]: [2015/07/17 09:34:33.386165,  0] printing/print_cups.c:528(cups_async_callback)
Jul 17 09:34:33 chttl-8a6e210a8d27536a smbd[1567]:   failed to retrieve printer list: NT_STATUS_UNSUCCESSFUL
Jul 17 09:47:34 chttl-8a6e210a8d27536a smbd[3272]: [2015/07/17 09:47:34.017469,  0] printing/print_cups.c:151(cups_connect)
Jul 17 09:47:34 chttl-8a6e210a8d27536a smbd[3272]:   Unable to connect to CUPS server localhost:631 - Connection refused
Jul 17 09:47:34 chttl-8a6e210a8d27536a smbd[1567]: [2015/07/17 09:47:34.017824,  0] printing/print_cups.c:528(cups_async_callback)
Jul 17 09:47:34 chttl-8a6e210a8d27536a smbd[1567]:   failed to retrieve printer list: NT_STATUS_UNSUCCESSFUL
Jul 17 10:00:34 chttl-8a6e210a8d27536a smbd[7256]: [2015/07/17 10:00:34.651162,  0] printing/print_cups.c:151(cups_connect)
Jul 17 10:00:34 chttl-8a6e210a8d27536a smbd[7256]:   Unable to connect to CUPS server localhost:631 - Connection refused
Jul 17 10:00:34 chttl-8a6e210a8d27536a smbd[1567]: [2015/07/17 10:00:34.651720,  0] printing/print_cups.c:528(cups_async_callback)
Jul 17 10:00:34 chttl-8a6e210a8d27536a smbd[1567]:   failed to retrieve printer list: NT_STATUS_UNSUCCESSFUL
Jul 17 10:13:35 chttl-8a6e210a8d27536a smbd[11582]: [2015/07/17 10:13:35.362361,  0] printing/print_cups.c:151(cups_connect)
Jul 17 10:13:35 chttl-8a6e210a8d27536a smbd[11582]:   Unable to connect to CUPS server localhost:631 - Connection refused
Jul 17 10:13:35 chttl-8a6e210a8d27536a smbd[1567]: [2015/07/17 10:13:35.362682,  0] printing/print_cups.c:528(cups_async_callback)
Jul 17 10:13:35 chttl-8a6e210a8d27536a smbd[1567]:   failed to retrieve printer list: NT_STATUS_UNSUCCESSFUL
Jul 17 10:26:35 chttl-8a6e210a8d27536a smbd[15564]: [2015/07/17 10:26:35.823554,  0] printing/print_cups.c:151(cups_connect)
Jul 17 10:26:35 chttl-8a6e210a8d27536a smbd[15564]:   Unable to connect to CUPS server localhost:631 - Connection refused
Jul 17 10:26:35 chttl-8a6e210a8d27536a smbd[1567]: [2015/07/17 10:26:35.823862,  0] printing/print_cups.c:528(cups_async_callback)
Jul 17 10:26:35 chttl-8a6e210a8d27536a smbd[1567]:   failed to retrieve printer list: NT_STATUS_UNSUCCESSFUL
Jul 17 10:39:36 chttl-8a6e210a8d27536a smbd[19370]: [2015/07/17 10:39:36.439927,  0] printing/print_cups.c:151(cups_connect)
Jul 17 10:39:36 chttl-8a6e210a8d27536a smbd[19370]:   Unable to connect to CUPS server localhost:631 - Connection refused
Jul 17 10:39:36 chttl-8a6e210a8d27536a smbd[1567]: [2015/07/17 10:39:36.440280,  0] printing/print_cups.c:528(cups_async_callback)
Jul 17 10:39:36 chttl-8a6e210a8d27536a smbd[1567]:   failed to retrieve printer list: NT_STATUS_UNSUCCESSFUL

I still don’t understand what this 631 port is for
I checked. Yes
Samba server is Unable to connect to CUPS Server localhost:631 — denied the connection
So this is a real problem. I didn’t use Samba in the first place, but then I thought, well, maybe it’s the Yamaxun server, so it’s a problem
To sum up, I still want to look at the log. I looked at the Apache log and the PHP log, but I forgot to look at the firewall log. I thought I wanted to open the ports, the results, or wrong, never think that to actually do it