Socket connection to port fails despite port open / listening !
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From: Jack on 19 Dec 2007 11:33 Hi all, I have opened port 5129 on 2 linux machines (CENTOS) and they are listening - 1 machine accepts socket connections from a third windows machine (all on same network) and the 1 doesnt !! What can I check ? 1- I ran this to verify ports: open(PRTCP,'/proc/net/tcp');while(<PRTCP>){ chomp;next if/^\s*$/;s/^\s*//;s/\s*$//;next if/^sl/;split/\s+/;@p=split':',$_[1];$h{hex $p[1]}=$_[7];}foreach(sort{$a<=>$b}keys%h){ print$_,"\t",[getpwuid($h{$_})]->[0],"\n"}; RESULT: 5129 jack 2- "netstat -tap" shows its listening : tcp 0 0 *:51295 *:* LIST EN 7379/jacksprogram 3- iptables: :INPUT ACCEPT [0:0] :FORWARD ACCEPT [0:0] :OUTPUT ACCEPT [0:0] :RH-Firewall-1-INPUT - [0:0] -A INPUT -j RH-Firewall-1-INPUT -A FORWARD -j RH-Firewall-1-INPUT -A RH-Firewall-1-INPUT -i lo -j ACCEPT -A RH-Firewall-1-INPUT -p icmp --icmp-type any -j ACCEPT -A RH-Firewall-1-INPUT -p 50 -j ACCEPT -A RH-Firewall-1-INPUT -p 51 -j ACCEPT -A RH-Firewall-1-INPUT -p udp --dport 5353 -d 224.0.0.251 -j ACCEPT -A RH-Firewall-1-INPUT -p udp -m udp --dport 631 -j ACCEPT -A RH-Firewall-1-INPUT -p tcp -m tcp --dport 631 -j ACCEPT -A RH-Firewall-1-INPUT -m state --state ESTABLISHED,RELATED -j ACCEPT -A RH-Firewall-1-INPUT -m state --state NEW -m tcp -p tcp --dport 22 - j ACCEPT -A RH-Firewall-1-INPUT -j REJECT --reject-with icmp-host-prohibited -A RH-Firewall-1-INPUT -m state --state NEW -m tcp -p tcp --dport 5129 -j ACCEPT COMMIT
From: Jack on 19 Dec 2007 11:35
On Dec 19, 8:33 am, Jack <jack_posem...(a)yahoo.com> wrote: > Hi all, > > I have opened port 5129 on 2 linux machines (CENTOS) and they are > listening - 1 machine accepts socket connections from a third windows > machine (all on same network) and the 1 doesnt !! What can I check ? > > 1- I ran this to verify ports: > open(PRTCP,'/proc/net/tcp');while(<PRTCP>){ > chomp;next if/^\s*$/;s/^\s*//;s/\s*$//;next > if/^sl/;split/\s+/;@p=split':',$_[1];$h{hex > $p[1]}=$_[7];}foreach(sort{$a<=>$b}keys%h){ > print$_,"\t",[getpwuid($h{$_})]->[0],"\n"}; > > RESULT: 5129 jack > > 2- "netstat -tap" shows its listening : > tcp 0 0 *:51295 > *:* LIST > EN 7379/jacksprogram > > 3- iptables: > :INPUT ACCEPT [0:0] > :FORWARD ACCEPT [0:0] > :OUTPUT ACCEPT [0:0] > :RH-Firewall-1-INPUT - [0:0] > -A INPUT -j RH-Firewall-1-INPUT > -A FORWARD -j RH-Firewall-1-INPUT > -A RH-Firewall-1-INPUT -i lo -j ACCEPT > -A RH-Firewall-1-INPUT -p icmp --icmp-type any -j ACCEPT > -A RH-Firewall-1-INPUT -p 50 -j ACCEPT > -A RH-Firewall-1-INPUT -p 51 -j ACCEPT > -A RH-Firewall-1-INPUT -p udp --dport 5353 -d 224.0.0.251 -j ACCEPT > -A RH-Firewall-1-INPUT -p udp -m udp --dport 631 -j ACCEPT > -A RH-Firewall-1-INPUT -p tcp -m tcp --dport 631 -j ACCEPT > -A RH-Firewall-1-INPUT -m state --state ESTABLISHED,RELATED -j ACCEPT > -A RH-Firewall-1-INPUT -m state --state NEW -m tcp -p tcp --dport 22 - > j ACCEPT > -A RH-Firewall-1-INPUT -j REJECT --reject-with icmp-host-prohibited > -A RH-Firewall-1-INPUT -m state --state NEW -m tcp -p tcp --dport 5129 > -j ACCEPT > COMMIT typocorrection to above, its port 5129, not 51295 - What else can I check ? A firewall config ? Something blocking TCP packets ? : 2- "netstat -tap" shows its listening : tcp 0 0 *:5129 *:* LIST EN 7379/jacksprogram |