On Tue, Apr 19, 2011 at 12:38 PM, JITHIN K <jithin...@gmail.com> wrote: > Hi, > > Please compare the latency variation etc > > 1. Network PC to ISP gateway > 2. Firewall to ISP gateway
Already did that. There is no difference . We have two switches between the firewall and the VC and there are not errors on the switch too. > > Regards, > Jithin K > > On Tue, Apr 19, 2011 at 7:55 AM, Girish Venkatachalam < > girishvenkatacha...@gmail.com> wrote: > >> On Mon, Apr 18, 2011 at 7:41 PM, Preetish <preetish.tripa...@gmail.com> >> wrote: >> > Hello Everybody >> > >> > I am not sure if this is the correct forum to discuss this so kindly >> > ignore this email if you find the topic irrelevant for this forum. >> >> Such long mails are a bore. It is like a novel. ;) >> >> Please write short sweet mails. >> >> > Recently we have started facing issue in our network where in if we >> > initiate a Video Conference ( we use Video Nation Life Size VC >> > equipment ) we see packet loss which goes upto 40% and jitters which >> > goes upto 100ms . This packet loss is only on incoming packets. So the >> > voice and video quality is very bad at our end however the person at >> > the other end is able to see and hear us very clearly. If we look at >> > the VC statistics, we can see that we are uploading at around 1 mbps >> > however the download starts at 1 mbps but then drops down to 100kbps >> > within seconds . Same is the case with skype calls . >> >> Good. ;) >> >> Normally download speeds are higher. >> >> > Now one of the reasons I am posting over here is that all our network >> > traffic goes via a debian box ( 5.0.4 ) which acts as the firewall. >> > The cpu utilization on the firewall is not high at all. This debian >> > box also acts as a vpn server and we have two VPN tunnel to connect to >> > our office in the UK . Also we use quagga ( ofpfd ) to route traffic >> > over the tunnels. Also I have checked statistics ( ethtool -S eth1 ) >> > of eth1 ( which is our internet link ) and it shows no error either on >> > rx or tx . All our internal network are on various vlans on eth2 and >> > there are no errors on it too. >> >> Good. >> >> > We have reported this issue to our ISP and they changed our route a >> > couple of times ( even the reverse route was changed ) however it did >> > not resolve the issue. Finally we bypassed our firewall and put the VC >> > equipment on a public IP ( its on a different subnet than our firewall >> > ) and we are not facing the issue any more ( I still have to check >> > which route it follows to the Video Nation gateway and compare it with >> > the route our firewall follows ) . >> >> Okay. >> >> > Now I know that there has been no change in our network which could >> > have caused this issue. However now the ISP says that the issue might >> > be because of our firewall . >> >> Quite possible. >> >> > Can someone let me know if there are any tools which can help me >> > troubleshoot this issue. Something that can let me know the point at >> > which there are packet loss. Also please let me know if I should be >> > looking at . >> >> There is not enough information in this mail albeit long. >> >> And this is a complex issue. >> >> Some ways to attack this are: >> >> 1) Try turning off connection tracking and other stuff in the Debian >> box and see >> how the network performs >> >> 2) Try a simple command line wget or something and find out what is >> happening. >> >> 3) Monitor the bandwidth in the Debian box and afterwards. Find out if >> something >> goes wrong in between >> >> There are 100 other ideas I can give. >> >> But you have to do it. >> >> -Girish >> >> >> -- >> G3 Tech >> Networking appliance company >> web: http://g3tech.in mail: gir...@g3tech.in >> _______________________________________________ >> ILUGC Mailing List: >> http://www.ae.iitm.ac.in/mailman/listinfo/ilugc >> > _______________________________________________ > ILUGC Mailing List: > http://www.ae.iitm.ac.in/mailman/listinfo/ilugc > _______________________________________________ ILUGC Mailing List: http://www.ae.iitm.ac.in/mailman/listinfo/ilugc
