similar to: Expected handling of [SYN] when expecting [SYN, ACK]?

Hi Tom, Many thanks for that, that''s really helped. Netfilter is indeed dropping the packets as invalid. Thanks and regards, Frances -----Original Message----- From: Tom Eastep [mailto:teastep@shorewall.net] Sent: 23 March 2007 18:05 To: Shorewall Users Subject: Re: [Shorewall-users] Expected handling of [SYN] when expecting[SYN, ACK]? Frances Flood wrote: > Basically, if the

I have a question about tcp layer of linux kernel. I want, Syn and ack packages received to server will be counted. [image: enter image description here] where total_syn_count and total_ack_count are variables to be defined and will be increased Which files to be used ???? tcp_input.c ,tcp_output.c , tcp_ipv4.c

I have found a very strange problem. We found that the time of establishing the websocket connection between mobile phone and server was too long. Then I use tcpdump to capture the data and found that the problem maybe has something to do with window scale option in SYN packet. Here is the SYN packet for websocket connection: 55488 ? 443 [SYN] Seq=0 Win=65535 Len=0 MSS=1460 WS=64

Hi, I''m interested in prioritizing all packets with the SYN bit on, both with and without the ACK bit on (but specially the SYN ACKS). I am checking is the use of Diffserv. From a paper I read I understood that when Diffserv is on, all "Control Traffic", including TCP SYN-ACKs, gets by default into "band 0" of Diffserv, the highest priority out of 16 bands. If true,

Hi...I've got two Grandstream phones attached to my Asterisk on the same subnet. The phones have fixed IP addresses. Asterisk is generated an error for one of them only, even though both appear to be registered correctly. The current state of the sip.conf is included below. Anyone know what is going on here? Both appear to be working fine between each other and between themselves in and

Now I step by step to configure Shorewall to match my school environment, the following error when I restart the Shorewall. ..End Macro iptables v1.2.11: Unknown arg `--sports'' Try `iptables -h'' or ''iptables --help'' for more information. ERROR: Command "/sbin/iptables -t nat -A loc_dnat -p tcp --sports !

Hi all, I have a VPN setup but it only works once in a while. It seems my firewall (shorewall 3.0.8) is blocking protocol 47. Here is what I have: eth0: internet eth2: dmz - my pptp server My entry In the rules file: pptp/ACCEPT fw dmz:192.168.253.2 My pptp macro ############################################################################### #ACTION SOURCE

Hello All, I know that this should be a trivial issue, but I''m stuck. I''m totally new to Shorewall and although I''ve read all about the zones, they''re still a bit confusing for me. What I''m attempting to do is run an FTP server on an internal machine. I''ve read the example guide and troubleshooting guide, but I can''t figure it

hi, Please see the following text diagram: 10.0.15.0/24 --> 10.0.15.1 (f0/1) cisco router (f0/0) 192.168.0.5 <-- 192.168.0.0/24 --> 192.168.0.1 firewall --> internet I have some problem after added a static route in shorewall in /etc/sysconfig/network-scripts/route-eth0, the syntax is: 10.0.15.0/24 via 192.168.0.5 in 192.168.0.0/24 computers cannot ping or

Hi all, I am having an issue with a multiple ISP setup. I have followed the docs online and I think I have everything setup correctly but I can get the desired traffice to go out my secondary ISP. A quick run down on what I am trying to acomplish. I want to send all sip/iax traffic out one ISP in the net zone and then send all other traffic out my secondary ISP in the dsl zone. Attached is

I just setup the Shorewall in my school, but now all clients can''t through to internet, all servers can through to internet with NAT, when I disabled NAT that all servers can''t through to internet. Below is my school network: internet ---> shorewall ----> loc ---> ciso router ---> loc1 Below is my config files: policy: # If you want to force clients to

Hi, How can only allow http,ftp,smtp define on outgoing rules ? Thanks _______________________________________ YM - 離線訊息 就算你沒有上網，你的朋友仍可以留下訊息給你，當你上網時就能立即看到，任何說話都冇走失。 http://messenger.yahoo.com.hk ------------------------------------------------------------------------- Take Surveys. Earn Cash. Influence the Future of IT Join SourceForge.net''s Techsay panel and

Hi When I start shorewall, the multicast stream is stopped. My config: Windows VLC Client-----eth0:192.168.254.1/24--fw---eth1:191.168.254.254/16-------------------------Linux VLC Streaming server 192.168.254/24 lan wan (but it''s really a internal lan !) 191.168.1.21/16 on the FW/shorewall route add -net 224.0.0.0 netmask

I have just finished a patch to linux 2.0.29 that provides the SYN cookies protection against SYN flood attacks. You can grab it from my home page at: http://www.dna.lth.se/~erics/software/tcp-syncookies-patch-1.gz You can also follow the pointers from my home page (see the signature) to get a very short blurb about this patch. Quick synopsys: This implements the SYN cookie defense against SYN

Hallo Group, i want to implement a syn Flood Protection on our linux Router. on our Cisco we have this Access-list and rat-limit rate-limit input access-group 190 128000 128000 128000 conform-action transmit exceed-action drop access-list 190 deny tcp any any established access-list 190 permit tcp any any access-list 190 deny ip any any now i was trying to wrote the same config with

Hi, sorry to bother you, and that this is probably not the right list :-), but I read that some of you might use syn as Editor for .R files. I've released an unofficial Version of the syn Text Editor with improved support for R (I'm the initial developer of this program, btw.). syn is a Windows 32 Program (Win9x, NT4, 2000), but maybe it runs also inside Wine, I didn't try it.

Anyone seen this problem? server Apr 16 14:34:28 nas1 kernel: [7506182.154332] TCP: TCP: Possible SYN flooding on port 49156. Sending cookies. Check SNMP counters. Apr 16 14:34:31 nas1 kernel: [7506185.142589] TCP: TCP: Possible SYN flooding on port 49157. Sending cookies. Check SNMP counters. Apr 16 14:34:53 nas1 kernel: [7506207.126193] TCP: TCP: Possible SYN flooding on port 49159. Sending

On 07/20/2018 03:56 AM, Leon Fauster via CentOS wrote: > Hi folks, > > I have here a database node running > > # rpm -qa | grep mysql-server > mysql55-mysql-server-5.5.52-1.el6.x86_64 > > on > > # virt-what > vmware > > > that seems to have a connection problem: > > # dmesg |grep SYN |tail -5 > possible SYN flooding on port 3306. Sending cookies.

On a Linux Server running tincd I noticed the following log message in /var/log/messages kernel: possible SYN flooding on port 655. Sending cookies. I found this on the web: If SYN cookies are enabled, then the kernel doesn't track half open connections at all. Instead it knows from the sequence number in the following ACK datagram that the ACK very probably follows a SYN and a SYN-ACK.

Check your slapd.conf ACL options. ____________________________________________________________________ --Forwarded Message Attachment-- From: fcd.listas@gmail.com Subject: [Samba] Samba + Ldap: password sync Date: Thu, 4 Oct 2007 15:19:42 -0300 To: samba@lists.samba.org Gentleman, While using Openldap 2.2.x, password syncronization was working fine. It means that when a user changed his