From soni_prash at yahoo.co.uk Sun Apr 16 22:25:40 2006 From: soni_prash at yahoo.co.uk (prashant soni) Date: Mon, 17 Apr 2006 06:25:40 +0100 (BST) Subject: [tg] about usage of dcat Message-ID: <20060417052540.8075.qmail@web25706.mail.ukl.yahoo.com> dear friends i m new usr of tg random packet generator.. i m novice here.. and facing problem in using dcat.. i simply downloaded binaries and sent random packets from 192.168.1.12 to 192.168.1.10 connected over crossover cable by ethernet nic.. here also it seems [ -o ] option for tg commond not worked..then i utilized tg < inputfile.tg > logser1.log then it worked.. after this i wanted to see logser1.log by dcat [prash at pglabpc10 linux]$ ./dcat [-a] /home/prash/logser1.log dcat cant open input : No such file or directory why it is happening..plzz give me hint..asap.. thanx.. Flying is learning how to throw yourself at the ground and miss. Prashant Soni Room No 330, Sarayu Hostel IIT Madras, Chennai - 36,mo no 09380552468 ___________________________________________________________ To help you stay safe and secure online, we've developed the all new Yahoo! Security Centre. http://uk.security.yahoo.com From b_a_denny at yahoo.com Mon Apr 17 11:27:03 2006 From: b_a_denny at yahoo.com (Barbara Denny) Date: Mon, 17 Apr 2006 11:27:03 -0700 (PDT) Subject: [tg] about usage of dcat In-Reply-To: <20060417052540.8075.qmail@web25706.mail.ukl.yahoo.com> Message-ID: <20060417182703.12527.qmail@web30106.mail.mud.yahoo.com> Hi, I am glad you are giving tg a try. I wanted to clarify that the square backets [] mean that the switch/flag is optional. So to use the -a option, the command is dcat -a filename. Please make sure the file exists and you are giving the correct path if it is not in your current working directory. You can also try the Unix command od with the -c switch (i.e. od -c) to try to see if the output file has been corrupted somehow. This file should begin with some ascii text. I also tested whether the -i and -o option work in tg. They did for me. Unless you tell me otherwise, I am assuming it is because you included the brackets when you gave the command which is incorrect. If it still doesn't work, please tell me what O.S you are trying to use. barbara --- prashant soni wrote: > dear friends > i m new usr of tg random packet generator.. > i m novice here.. > and facing problem in using dcat.. > i simply downloaded binaries and sent random packets > from > 192.168.1.12 to 192.168.1.10 connected over > crossover > cable by ethernet nic.. > here also it seems [ -o ] option for tg commond not > worked..then i utilized > tg < inputfile.tg > logser1.log > then it worked.. > after this i wanted to see logser1.log by dcat > [prash at pglabpc10 linux]$ ./dcat [-a] > /home/prash/logser1.log > dcat cant open input : No such file or directory > > why it is happening..plzz give me hint..asap.. > thanx.. > > > Flying is learning how to throw yourself at the > ground and miss. > Prashant Soni > Room No 330, Sarayu Hostel > IIT Madras, Chennai - 36,mo no 09380552468 > > > > > > ___________________________________________________________ > > To help you stay safe and secure online, we've > developed the all new Yahoo! Security Centre. > http://uk.security.yahoo.com > _______________________________________________ > tg mailing list > tg at postel.org > http://www.postel.org/mailman/listinfo/tg > From soni_prash at yahoo.co.uk Mon Apr 17 22:03:26 2006 From: soni_prash at yahoo.co.uk (prashant soni) Date: Tue, 18 Apr 2006 05:03:26 +0000 (GMT) Subject: [tg] abt srource IP addr in server log.. Message-ID: <20060418050326.39587.qmail@web25708.mail.ukl.yahoo.com> dear barbara thnx it seems it will work for me as u have rightly pointed out abt [ ].. one more problem i am facing.. actually i have set a kind of demonstration for redundent communication between two Fedora core3 machines connected through two crossover cable (one primary another secondary channel) Two NIC in each comp..Two IP for each comp... now data usually goes thru primary srource IP , (primary cable.) and .if i unplug it it goes thru secondary channel (cable)..thru secondary srs IP.. to destination.. [ little static routing table database trick ] n it works for UDP..for TCP applications it requires resession setup.. now my problem is when i use TG for generating random UDP packets at server log it shows only one srs IP address..though i have unpluged that cable n data r coming from secondary cable thru seconadry NIC.. TG server log shows same IP for source..why ????? hope i m clear in my question.. for TCP application .. resession setup how could i employ in TG whenever primary chennel goes out...some hints r welcome thanx.. Flying is learning how to throw yourself at the ground and miss. Prashant Soni Room No 330, Sarayu Hostel IIT Madras, Chennai - 36,mo no 09380552468 From soni_prash at yahoo.co.uk Tue Apr 18 02:05:44 2006 From: soni_prash at yahoo.co.uk (prashant soni) Date: Tue, 18 Apr 2006 09:05:44 +0000 (GMT) Subject: [tg] abt srource IP addr in server log.. Message-ID: <20060418090544.78734.qmail@web25703.mail.ukl.yahoo.com> dear barbara thnx it seems it will work for me as u have rightly pointed out abt [ ] in using options,.. one more problem i am facing.. actually i have set a kind of demonstration for redundent communication between two Fedora core3 machines connected through two crossover cable (one primary another secondary channel) Two NIC in each comp..Two IP for each comp... now data usually goes thru primary srource IP , (primary cable.) and .if i unplug it it goes thru secondary channel (cable)..thru secondary srs IP.. to destination.. [ little static routing table database trick ] n it works for UDP..for TCP applications it requires resession setup.. now my problem is when i use TG for generating random UDP packets at server log it shows only one srs IP address..though i have unpluged that cable n data r coming from secondary cable thru seconadry NIC.. TG server log shows same IP for source..why ????? hope i m clear in my question.. for TCP application .. resession setup how could i employ in TG whenever primary chennel goes out...some hints r welcome thanx.. Flying is learning how to throw yourself at the ground and miss. Prashant Soni Room No 330, Sarayu Hostel IIT Madras, Chennai - 36,mo no 09380552468 _______________________________________________ tg mailing list tg at postel.org http://www.postel.org/mailman/listinfo/tg From b_a_denny at yahoo.com Wed Apr 19 16:40:47 2006 From: b_a_denny at yahoo.com (Barbara Denny) Date: Wed, 19 Apr 2006 16:40:47 -0700 (PDT) Subject: [tg] abt srource IP addr in server log.. In-Reply-To: <20060418090544.78734.qmail@web25703.mail.ukl.yahoo.com> Message-ID: <20060419234047.13754.qmail@web30111.mail.mud.yahoo.com> Hello, You must remember TG is only a user process. Whatever happens regarding source address selection takes place in the kernel if you have not specified it. It is possible to tell the kernel which source address you want to use if their are multiple ones. In TG there is undocumented feature of giving 2 IP addresses in the association spec. The first one is the source; the second is the destination. Glancing at the code, it looks like it is set up to work with udp, but not tcp (testing also seems to verify this). If you really want to force the binding to a particular source address when you BEGIN the tcp connection, you can modify the code (see prot_dgram.c for an example. The change would be made in prot_stream.c). I might be able to make the change and test it out soon to verify it works for TCP.I just don't have the time today and I won't have the time to do an official release of TG soon. Remember on the receive side you can use INADDR_ANY (0.0.0.0) in the script to accept the "connection" from any address. The source address of the data flow will be recorded in the ouput file for the data sink. If the source address doesn't change when you are using udp, I imagine this is just the way things work in the linux kernel. Even though the path is now through you other link, the source address doesn't get modified. I don't have the resources to replicate your test case. I am not sure what you asking me regarding ressession setup with TCP. I am not sure exactly what you are trying to do and what behaviour you are seeing. If the TCP connection breaks when you change links, myy immediate reaction is to think the problem you are having with TG and TCP has nothing to do with TG and TG cannot "fix" it. It has to do with the Internet architecture. TCP uses the IP address to help identify the connection. If you do something to force the IP address to "change", you will cause the connection to break. However, maybe you want to do something else but I need to understand what that is. Right now I don't know. Now if the kernel really doesn't bother to "invalidate" the source address when it uses a different interface then there is a chance the tcp connection won't break. Again, I don't have the resources to replicate your test. You could try running tcpdump to see what goes on the wire in the udp and tcp case. It is interesting that you are reporting that UDP doesn't change its source address when you cause packets to use the other link. This would make me think that the TCP connection might have a chance of staying up. Now whether this is the correct behavior is another question... Overall it sounds like you are trying to show some type of fault tolerant behavior, versus emulating mobility. In some ways, the problem is similar so I suggest looking into those areas to deepen your understanding. There probably is also some discussion of it under the topic of multihoming too. barbara --- prashant soni wrote: > > dear barbara > thnx it seems it will work for me as u have rightly > pointed out abt [ ] in using options,.. > > one more problem i am facing.. > > actually i have set a kind of demonstration for > redundent communication between two Fedora core3 > machines connected through two crossover cable (one > primary another secondary channel) Two NIC in each > comp..Two IP for each comp... > now data usually goes thru primary srource IP , > (primary cable.) and .if i unplug it it goes thru > secondary channel (cable)..thru secondary srs IP.. > to destination.. > [ little static routing table database trick ] > n it works for UDP..for TCP applications it > requires resession setup.. > > now my problem is when i use TG for generating > random UDP packets at server log it shows only one > srs IP address..though i have unpluged that cable n > data r coming from secondary cable thru seconadry > NIC.. TG server log shows same IP for source..why > ????? > hope i m clear in my question.. > > for TCP application .. resession setup how could i > employ in TG whenever primary chennel goes > out...some hints r welcome > > thanx.. > > Flying is learning how to throw yourself at the > ground and miss. > Prashant Soni > Room No 330, Sarayu Hostel > IIT Madras, Chennai - 36,mo no 09380552468 > _______________________________________________ > tg mailing list > tg at postel.org > http://www.postel.org/mailman/listinfo/tg > _______________________________________________ > tg mailing list > tg at postel.org > http://www.postel.org/mailman/listinfo/tg > From b_a_denny at yahoo.com Thu Apr 20 09:09:04 2006 From: b_a_denny at yahoo.com (Barbara Denny) Date: Thu, 20 Apr 2006 09:09:04 -0700 (PDT) Subject: [tg] abt srource IP addr in server log.. - Correction In-Reply-To: <20060419234047.13754.qmail@web30111.mail.mud.yahoo.com> Message-ID: <20060420160904.73255.qmail@web30101.mail.mud.yahoo.com> Hi, I made a mistake in my last email message. The file to modify is prot_tcp.c if you want to select the TCP source address. See prot_udp.c for an example. I did test it for TCP and it worked. barbara