My random inaccessibility of PPRuNE!
Controversial, moi?
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My random inaccessibility of PPRuNE!
I have a really strange problem that started about 6 months ago. I will be happily surfing PPRuNe and will without warning get a page unavailable warning. i.e Internet Explorer tells me that the page cannot be found or the site is unavailable, I cannot remember the exact wording.
I then find that access is unavailable for periods ranging from days to several weeks.
I have no virii, I regularly clear out junk cookies and other miscellaneous rubbish.
My broadband ISP asked me to do some ping and trace route tests. They concluded that:
'The fact that you're getting out of the Nildram network all the way to theirs shows that the routing is ok so it looks like they're blocking you their end. I notice they're a forum so its quite likely that they've blacklisted your IP (perhaps for content of posts or something). I would suggest contacting them directly.'
I contacted PPRuNE via a moderator and am assured that I am not being blocked.
The results of the last trace when I was blocked last earlier this week are:
Tracing route to www.pprune.org [209.25.220.53]
over a maximum of 30 hops:
1 <10 ms <10 ms <10 ms 192.168.0.1
2 16 ms 31 ms 16 ms lon1-adsl2.nildram.net [195.149.20.12]
3 15 ms 31 ms 16 ms lon1-9.nildram.net [213.208.106.194]
4 15 ms 32 ms 15 ms lndnuk1icx1.wcg.net [195.66.224.105]
5 172 ms 156 ms 172 ms nycmny2wcx2-oc12.wcg.net [64.200.87.149]
6 171 ms 157 ms 172 ms nycmny2wcx3-oc48.wcg.net [64.200.87.78]
7 172 ms 156 ms 172 ms chcgil1wcx3-oc48.wcg.net [64.200.240.37]
8 156 ms 172 ms 156 ms brvwil1wcxa-pos9-0.wcg.net [64.200.103.193]
9 172 ms 156 ms 172 ms dnvrco1wcx2-pos10-0.wcg.net [64.200.210.66]
10 172 ms 156 ms 172 ms snfcca1wcx3-pos11-0.wcg.net [64.200.240.94]
11 172 ms 156 ms 156 ms sntcca1wcx1-oc48.wcg.net [64.200.151.93]
12 172 ms 156 ms 156 ms sntcca1wcx1-hostcentric-gige.wcg.net [64.200.150.66]
13 156 ms 172 ms 156 ms ATM3-0.FMT-1.hostcentric.com [209.25.214.118]
14 281 ms 156 ms 156 ms VLAN12.FMT6509-2.hostcentric.com [66.40.24.74]
15 * * * Request timed out.
16 * * * Request timed out.
17 * * * Request timed out.
18 * * * Request timed out.
19 * * * Request timed out.
20 * * * Request timed out.
21 * * * Request timed out.
22 * * * Request timed out.
23 * * * Request timed out.
24 * * * Request timed out.
25 * * * Request timed out.
26 * * * Request timed out.
27 * * * Request timed out.
28 * * * Request timed out.
29 * * * Request timed out.
30 * * * Request timed out.
Trace complete.
It all means nothing to me.
Does anybody have any ideas please?
I then find that access is unavailable for periods ranging from days to several weeks.
I have no virii, I regularly clear out junk cookies and other miscellaneous rubbish.
My broadband ISP asked me to do some ping and trace route tests. They concluded that:
'The fact that you're getting out of the Nildram network all the way to theirs shows that the routing is ok so it looks like they're blocking you their end. I notice they're a forum so its quite likely that they've blacklisted your IP (perhaps for content of posts or something). I would suggest contacting them directly.'
I contacted PPRuNE via a moderator and am assured that I am not being blocked.
The results of the last trace when I was blocked last earlier this week are:
Tracing route to www.pprune.org [209.25.220.53]
over a maximum of 30 hops:
1 <10 ms <10 ms <10 ms 192.168.0.1
2 16 ms 31 ms 16 ms lon1-adsl2.nildram.net [195.149.20.12]
3 15 ms 31 ms 16 ms lon1-9.nildram.net [213.208.106.194]
4 15 ms 32 ms 15 ms lndnuk1icx1.wcg.net [195.66.224.105]
5 172 ms 156 ms 172 ms nycmny2wcx2-oc12.wcg.net [64.200.87.149]
6 171 ms 157 ms 172 ms nycmny2wcx3-oc48.wcg.net [64.200.87.78]
7 172 ms 156 ms 172 ms chcgil1wcx3-oc48.wcg.net [64.200.240.37]
8 156 ms 172 ms 156 ms brvwil1wcxa-pos9-0.wcg.net [64.200.103.193]
9 172 ms 156 ms 172 ms dnvrco1wcx2-pos10-0.wcg.net [64.200.210.66]
10 172 ms 156 ms 172 ms snfcca1wcx3-pos11-0.wcg.net [64.200.240.94]
11 172 ms 156 ms 156 ms sntcca1wcx1-oc48.wcg.net [64.200.151.93]
12 172 ms 156 ms 156 ms sntcca1wcx1-hostcentric-gige.wcg.net [64.200.150.66]
13 156 ms 172 ms 156 ms ATM3-0.FMT-1.hostcentric.com [209.25.214.118]
14 281 ms 156 ms 156 ms VLAN12.FMT6509-2.hostcentric.com [66.40.24.74]
15 * * * Request timed out.
16 * * * Request timed out.
17 * * * Request timed out.
18 * * * Request timed out.
19 * * * Request timed out.
20 * * * Request timed out.
21 * * * Request timed out.
22 * * * Request timed out.
23 * * * Request timed out.
24 * * * Request timed out.
25 * * * Request timed out.
26 * * * Request timed out.
27 * * * Request timed out.
28 * * * Request timed out.
29 * * * Request timed out.
30 * * * Request timed out.
Trace complete.
It all means nothing to me.
Does anybody have any ideas please?
Join Date: Mar 2002
Location: London, UK
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Unfortunately, all you can conclude from that is that pings are being blocked 
(which, these days, is not unreasonable.)
pings (or ICMP echo requests, to give them their proper name
) are (were) a useful way of testing internet connectivity. Too, useful, it turns out. That is, they could be used by the bad guys(TM) as well as the good guys, to find things out about your network, often as a prelude to a hacking attempt. So most sites block pings at their gateways, these days.
So are pings any use ? Certainly "inside" your network (whatever that may be) they can be very useful. Across the public internet ? well, if a ping suceeds, you definitely have reacability. If it doesn't, you haven't proved anything one way or the other
Back to the main point of the thread, I've no idea, offhand, what your problem is (but you've managed to post this .) The fact that you can get as far as VLAN12.FMT6509-2.hostcentric.com indicates that you have got connectivity as far as hostcentric, the colo providers for prune, and that pings are being blocked from that point (see above.) All of which would indicate a problem either with connectivity inside hostcentric, or actual server problems/downtime on prune itself.
I have noticed that prune has been a little up and down recently, but it would be very churlish of me to complain, since the whole thing is run for free to us by some very dedicated volunteers. Thanks to all who make it possible
HTH,
RTFM
(which, these days, is not unreasonable.)pings (or ICMP echo requests, to give them their proper name
) are (were) a useful way of testing internet connectivity. Too, useful, it turns out. That is, they could be used by the bad guys(TM) as well as the good guys, to find things out about your network, often as a prelude to a hacking attempt. So most sites block pings at their gateways, these days. So are pings any use ? Certainly "inside" your network (whatever that may be) they can be very useful. Across the public internet ? well, if a ping suceeds, you definitely have reacability. If it doesn't, you haven't proved anything one way or the other
Back to the main point of the thread, I've no idea, offhand, what your problem is (but you've managed to post this
.) The fact that you can get as far as VLAN12.FMT6509-2.hostcentric.com indicates that you have got connectivity as far as hostcentric, the colo providers for prune, and that pings are being blocked from that point (see above.) All of which would indicate a problem either with connectivity inside hostcentric, or actual server problems/downtime on prune itself.I have noticed that prune has been a little up and down recently, but it would be very churlish of me to complain, since the whole thing is run for free to us by some very dedicated volunteers. Thanks to all who make it possible
HTH,
RTFM
Join Date: May 2002
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To add to RTFM's very detailed reply ;
You were only 1 further hop away from www.pprune.org.
The site does not appear to block ICMP mesages (Pings, tracert and the like) - some do, some don't, often depends on type of firewall being used at the remote end.
I reached the site today, consistently in an average of 156ms, 17 hops from the UK and nil timeouts.
This would certainly suggest that your particular IP address could be blocked, but you have eliminated that possibility. If that was the case then you would never get access.
Makes me think about timing issues with your browser or local ISP connection. You are Broadband which makes me wonder what browser you are using ?
Now where did I put my Sniffer ? .....
You were only 1 further hop away from www.pprune.org.
The site does not appear to block ICMP mesages (Pings, tracert and the like) - some do, some don't, often depends on type of firewall being used at the remote end.
I reached the site today, consistently in an average of 156ms, 17 hops from the UK and nil timeouts.
This would certainly suggest that your particular IP address could be blocked, but you have eliminated that possibility. If that was the case then you would never get access.
Makes me think about timing issues with your browser or local ISP connection. You are Broadband which makes me wonder what browser you are using ?
Now where did I put my Sniffer ? .....
Controversial, moi?
Thread Starter
Internet Explorer Version 6.0.2800.1106 is my browser but when access is denied Opera doesn't have any luck either.
I spend (waste) many hours on the internet and this is my only recurring problem.
My understanding of pings and traceroutes is limited to say the least but I understood the gist of your posts.
It is random and bizarre but thanks for your thoughts anyway.
And in answer to the observation my access returned last night after 4 days away!
I spend (waste) many hours on the internet and this is my only recurring problem.
My understanding of pings and traceroutes is limited to say the least but I understood the gist of your posts.
It is random and bizarre but thanks for your thoughts anyway.
And in answer to the observation my access returned last night after 4 days away!
Join Date: Mar 2002
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OK, so do some forensics 
Run a few traceroutes when connectivity is OK. Save them for reference (multiple runs may be somewhat different when things are working OK -- that's the internet at work.)
Then when Prune "breaks", run a ping again and compare. Substantial differences may indicate a connectivity/routing problem. Unfortueately, the law of murphy, being what it is, the "fault" will be at neither your ISP's end, nor the prune end, but at some vague indeterminate place in between, where it's not obvious who to report the problem to
Run a few traceroutes when connectivity is OK. Save them for reference (multiple runs may be somewhat different when things are working OK -- that's the internet at work.)
Then when Prune "breaks", run a ping again and compare. Substantial differences may indicate a connectivity/routing problem. Unfortueately, the law of murphy, being what it is, the "fault" will be at neither your ISP's end, nor the prune end, but at some vague indeterminate place in between, where it's not obvious who to report the problem to
The Oracle
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M.Mouse,
How do you connect to the internet?
Do you see pages unavailable during peak times for internet usage or is it at all times of the day?
Take Care,
Richard
How do you connect to the internet?
Do you see pages unavailable during peak times for internet usage or is it at all times of the day?
Take Care,
Richard
Join Date: Sep 2002
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There are some times when PPRuNe really seems to be down (no posts on the forums when it comes back up again), but I've also been seeing some connection problems from work (but not home) - the reason has turned out to be that one of the boxes in our load-balancing internet proxy is a bit dodgy. If you go via that one then the HTTP request tends to fail and/or give off Zeus malformed request exceptions. If it decided to route you via a different box then things are fine. There's some kind of IP-affinity built in, so you will tend to be routed through the same box for a while - and if it's the duff one, no PPRuNe for a bit But it tends to be minutes/hours, not days
It's possible that your ISP is running a similar setup - it's good for them, because the more they can cache the less bandwidth they need. Not sure that your tracert agrees though.
But it tends to be minutes/hours, not days It's possible that your ISP is running a similar setup - it's good for them, because the more they can cache the less bandwidth they need. Not sure that your tracert agrees though.
Controversial, moi?
Thread Starter
Richard
I have an ADSL connection and never really experience any major fluctuations in speed or accessibility of any of my regular sites, just PPRuNe will at random not be available for periods of a few days to a few weeks.
RTFM
Thanks for that idea I will try it.
I have an ADSL connection and never really experience any major fluctuations in speed or accessibility of any of my regular sites, just PPRuNe will at random not be available for periods of a few days to a few weeks.
RTFM
Thanks for that idea I will try it.
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I just tracerted pprune.org and it timed out at the same point as M.Mouse's. However pprune pinged ok.
Why would one work and not the other, as both are just sending ICMP packets, aren't they?
AA
Why would one work and not the other, as both are just sending ICMP packets, aren't they?
AA
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I must say that I experience exactly the same problems- Pprune being the only website which I can't access for several hours at a time. This occurs randomly at 1-2 weekly intervals). Last night being the last period of no access.
Probably due to maintenance (although there's usually a maintenance notice notifying us that works are being carried out)
Any thoughts from the Tech moderators?
Probably due to maintenance (although there's usually a maintenance notice notifying us that works are being carried out)
Any thoughts from the Tech moderators?
Last edited by Tosh McCaber; 7th Sep 2003 at 20:09.
Controversial, moi?
Thread Starter
Once again I couldn't gain access from around 1700 on 1st September until today!
My ISP is adamant that I am being blocked but that the problem is not with them.
Nobody at PPRuNe seems able to help but this is driving me nuts and everybody seems to claim the problem is not them!
My ISP is adamant that I am being blocked but that the problem is not with them.
Nobody at PPRuNe seems able to help but this is driving me nuts and everybody seems to claim the problem is not them!
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Hi there. I would ask your neighbour if they can log on, that is presuming you have a neighbour that is on-line. If they can log-on ok then consider another phone line to your house just for the internet.
I have noticed recently that pprune has been down a few times and when I have logged on there is a big gap in the times of posts on my forum. This has happened quite a lot recently so I don't know if it is a local problem or not. Maybe Danny or Mik can tell us if they are aware of anything like this.
I have noticed recently that pprune has been down a few times and when I have logged on there is a big gap in the times of posts on my forum. This has happened quite a lot recently so I don't know if it is a local problem or not. Maybe Danny or Mik can tell us if they are aware of anything like this.
Join Date: May 2002
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M. Mouse - I have exactly the same problem. Just gained access after 4 days of 'website not found' or 'connection refused'.
Not impressed and it's definitely a problem within the workings of the PPRUNE host and/or network.
Not impressed and it's definitely a problem within the workings of the PPRUNE host and/or network.
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I had the same problem here on Sunday last. Feeling withdrawl symtoms I used some tracing tools I use at work to see if I could find out were the problem was.
The upshot was that I was able to trace the route all the way to Hostcentric (prune's hosting provider). The problem IS with hostcentric and I feel the senior mods need ask Hostcentric some hard questions. Got a nasty feeling that they have some peering issues. Senior MOD''s get on em hard and find out what is going on as this is not isolated.
I'm with pipex ADSL if thats's any help.
The upshot was that I was able to trace the route all the way to Hostcentric (prune's hosting provider). The problem IS with hostcentric and I feel the senior mods need ask Hostcentric some hard questions. Got a nasty feeling that they have some peering issues. Senior MOD''s get on em hard and find out what is going on as this is not isolated.
I'm with pipex ADSL if thats's any help.
