Re: Parts of the internet keep on disappearing on me

2013-01-27 Thread Shachar Shemesh
On 01/27/2013 10:56 AM, Noam Meltzer wrote: > > > On Thu, Jan 24, 2013 at 8:54 AM, Shachar Shemesh > wrote: > > Hail the conquering hero! > > Color me dumbfounded. Disabling TCP timestamps actually allows me > to connect to Google. Reenabling them re-introdu

Re: Parts of the internet keep on disappearing on me

2013-01-27 Thread Noam Meltzer
On Thu, Jan 24, 2013 at 8:54 AM, Shachar Shemesh wrote: > Hail the conquering hero! > > Color me dumbfounded. Disabling TCP timestamps actually allows me to > connect to Google. Reenabling them re-introduces the problem. > Shachar, have you disabled the TCP timestamps on your "problematic" PC or

Re: Parts of the internet keep on disappearing on me

2013-01-26 Thread shimi
On Thu, Jan 24, 2013 at 2:53 PM, Shachar Shemesh wrote: > On 01/24/2013 02:44 PM, E.S. Rosenberg wrote: > > > > When you enable timestamps they don't match so the packet is discarded, this > could be due to the ISP fiddling with the packets on the way. > > I know what timestamp is, and what it

Re: Parts of the internet keep on disappearing on me

2013-01-24 Thread Shachar Shemesh
On 01/24/2013 02:44 PM, E.S. Rosenberg wrote: > > > When you enable timestamps they don't match so the packet is discarded, this > could be due to the ISP fiddling with the packets on the way. I know what timestamp is, and what it is used for. I have not, yet, rebooted to see whether this does not

Re: Parts of the internet keep on disappearing on me

2013-01-24 Thread E.S. Rosenberg
>From the RFC (http://www.networksorcery.com/enp/rfc/rfc1323.txt): TCP Timestamps Option (TSopt): Kind: 8 Length: 10 bytes +---+---+-+-+ |Kind=8 | 10 | TS Value (TSval) |TS Echo Reply (TSecr)|

Re: Parts of the internet keep on disappearing on me

2013-01-24 Thread Shachar Shemesh
On 01/24/2013 10:04 AM, shimi wrote: > > > On Thu, Jan 24, 2013 at 8:54 AM, Shachar Shemesh > wrote: > > Hail the conquering hero! > > Color me dumbfounded. Disabling TCP timestamps actually allows me > to connect to Google. Reenabling them re-introduces the

Re: Parts of the internet keep on disappearing on me

2013-01-24 Thread E.S. Rosenberg
The TSecr value/field in the return packet from google is wrong, it should be identical to the timestamp you sent and it is not. 2013/1/24 shimi > > > On Thu, Jan 24, 2013 at 8:54 AM, Shachar Shemesh wrote: > >> Hail the conquering hero! >> >> Color me dumbfounded. Disabling TCP timestamps act

Re: Parts of the internet keep on disappearing on me

2013-01-24 Thread shimi
On Thu, Jan 24, 2013 at 8:54 AM, Shachar Shemesh wrote: > Hail the conquering hero! > > Color me dumbfounded. Disabling TCP timestamps actually allows me to > connect to Google. Reenabling them re-introduces the problem. > > The only question still remaining is "why"? I have up on the site two >

Re: Parts of the internet keep on disappearing on me

2013-01-23 Thread Shachar Shemesh
Hail the conquering hero! Color me dumbfounded. Disabling TCP timestamps actually allows me to connect to Google. Reenabling them re-introduces the problem. The only question still remaining is "why"? I have up on the site two captures. One of the working session, and one of the not working sessi

Re: Parts of the internet keep on disappearing on me

2013-01-23 Thread Amos Shapira
Another thing to verify is whether your packets get tweaked by anything on the way - when you see the three-way handshake you just described - was the packet size, number, serial numbers and flags received exactly as they were sent or can you identify packets being sent more times than received, or

Re: Parts of the internet keep on disappearing on me

2013-01-22 Thread Shachar Shemesh
On 01/20/2013 10:59 PM, shimi wrote: > > > Does ping work when the internet is 'down'? If so, I would go for: > > TCP Timestamps, TCP SYN Cookies, Selective ACKs, Window Scaling SYN cookies are irrelevant here, as my machine is the one initiating the connection. I am not sure what the question is r

Re: Parts of the internet keep on disappearing on me

2013-01-22 Thread E.S. Rosenberg
Could it be that you have a lot of traffic coming out of your station and you are running out of available tcp/udp ports (in bridged mode the VMs would not be using ports as their traffic is practically direct with the NIC, but in NAT mode they would be taking up TCP/UDP ports on your host machine)

Re: Parts of the internet keep on disappearing on me

2013-01-22 Thread Shachar Shemesh
On 01/22/2013 04:22 PM, Baruch Shpirer wrote: > > Are all vms running same os? > My host machine is Debian Squeeze with kernel from backports. My VM is an Ubuntu server 12.10 (kernel 3.4, IIRC). Also, I have some more orderly collected information. All attempts are for connecting to my own server

Re: Parts of the internet keep on disappearing on me

2013-01-22 Thread Baruch Shpirer
Are all vms running same os? On Jan 22, 2013 1:09 AM, "Shachar Shemesh" wrote: > I'll try to summarize in a single reply. > > You all made some very good suggestions, that are irrelevant for my case, > I'm afraid. > > This is not the NIC. It's not its hardware or driver or firmware. > Otherwise,

Re: Parts of the internet keep on disappearing on me

2013-01-22 Thread Geoffrey S. Mendelson
E.S. Rosenberg wrote: Even though you say it is not your DNS provider, please note that unless you manually set something else the Bezeq modem are notoriously unreliable in my experience, they can be acting fine with one computer in their network and almost completely barring access from anothe

Re: Parts of the internet keep on disappearing on me

2013-01-22 Thread E.S. Rosenberg
Even though you say it is not your DNS provider, please note that unless you manually set something else the Bezeq modem are notoriously unreliable in my experience, they can be acting fine with one computer in their network and almost completely barring access from another machine. 2013/1/22

Re: Parts of the internet keep on disappearing on me

2013-01-21 Thread Shachar Shemesh
I'll try to summarize in a single reply. You all made some very good suggestions, that are irrelevant for my case, I'm afraid. This is not the NIC. It's not its hardware or driver or firmware. Otherwise, the virtual machine would have experienced the same problem when bridging, and it doesn't. D

Re: Parts of the internet keep on disappearing on me

2013-01-21 Thread Steve G.
I sometimes observe something similar, and my feeling it has to do with the DNS of my provider. I try to reach a place and it hangs. Then if I run a terminal program that gets me the ip address, there is no problem. Ditto if I reload the page. I think - no proof - that my provider's DNS is too slo

Re: Parts of the internet keep on disappearing on me

2013-01-21 Thread Baruch Shpirer
Nothing in dmesg? Which nic hw and fw and driver version + kernel? Stats on nic Using nm? On Jan 20, 2013 2:49 PM, "Shachar Shemesh" wrote: > Hi all, > > I have a really strange problem. On one of the computers in my house, > parts of the internet keep on disappearing. Sometimes half the interne

Re: Parts of the internet keep on disappearing on me

2013-01-20 Thread shimi
On Sun, Jan 20, 2013 at 9:49 PM, Shachar Shemesh wrote: > Hi all, > > I have a really strange problem. On one of the computers in my house, > parts of the internet keep on disappearing. Sometimes half the internet is > inaccessible, and sometimes it's just a couple of sites (google is a > favorit

Re: Parts of the internet keep on disappearing on me

2013-01-20 Thread Omer Zak
More stupid questions: * Did you check maximum packet size and fragmenting? * Does the problematic machine have a "strange" network card (in "strange" I mean a rarely used network card, whose driver has higher probability of having bugs)? * Do firewalls between the problematic machine and the Inter

Re: Parts of the internet keep on disappearing on me

2013-01-20 Thread Josh Amishav-Zlatin
On Sun, Jan 20, 2013 at 10:01 PM, Shachar Shemesh wrote: > On 01/20/2013 09:55 PM, yochai wrote: > > I know it's a basic question, but did you check that you have no issue > with resolving domains while the computer doesn't work properly ? > > The problems happen even if name resolution succeede

Re: Parts of the internet keep on disappearing on me

2013-01-20 Thread Shachar Shemesh
On 01/20/2013 09:55 PM, yochai wrote: > I know it's a basic question, but did you check that you have no issue > with resolving domains while the computer doesn't work properly ? The problems happen even if name resolution succeeded. As far as I can tell, the name resolution problems, when they hap

Re: Parts of the internet keep on disappearing on me

2013-01-20 Thread yochai
I know it's a basic question, but did you check that you have no issue with resolving domains while the computer doesn't work properly ? On 01/20/2013 09:49 PM, Shachar Shemesh wrote: > Hi all, > > I have a really strange problem. On one of the computers in my house, > parts of the internet keep

Parts of the internet keep on disappearing on me

2013-01-20 Thread Shachar Shemesh
Hi all, I have a really strange problem. On one of the computers in my house, parts of the internet keep on disappearing. Sometimes half the internet is inaccessible, and sometimes it's just a couple of sites (google is a favorite for this problem). This is, most definitely, NOT a router or ISP p