Slow Forums: PF Under DDOS Attack

  • Thread starter Thread starter Borek
  • Start date Start date
  • #331
Seems like it is not the first time when there is a (routing?) problem at 66.228.118.190.

Sometimes pings to PF get through, sometimes they don't, but I can't reach PF by traceroute and I can't post/read without a proxy.
 
Physics news on Phys.org
  • #332
I had similar problems with 66.228.118.186 last Saturday.
 
  • #333
I have Avast and I have not seen any popups when visiting PF.
 
  • #334
The forum is a bit slow this afternoon.

Or perhaps my brain is extra fast :biggrin:!

Hmm...no, it's the forum. Dang.
 
  • #335
Sunday afternoon/evening, PF died for me. I don't know if this was a widespread issue or if there were issues on the path between here and there.
 
  • #338
Is it just me, or is the forum slow today? For most of the time it goes OK, but then for a minute or two it freezes.
 
  • #339
Borek said:
Is it just me, or is the forum slow today? For most of the time it goes OK, but then for a minute or two it freezes.

Right now the forum is responsive.
But earlier today I got a couple of gateway timeouts that other people apparently didn't have.
When I watched what my browser was doing before a timeout, I saw that it happened when it was accessing mathjax.org...
I'm not sure yet however, that mathjax.org is the reason...
 
  • #340
I like Serena said:
Right now the forum is responsive.
But earlier today I got a couple of gateway timeouts that other people apparently didn't have.
When I watched what my browser was doing before a timeout, I saw that it happened when it was accessing mathjax.org...
I'm not sure yet however, that mathjax.org is the reason...

Yep, I got that too, a few times now. I'm using Chrome, and I get a message I've never seen before that mentioned mathjax. Nothing is responsive, not even the cursor. Lasts about 10 seconds.
 
  • #341
lisab said:
Yep, I got that too, a few times now. I'm using Chrome, and I get a message I've never seen before that mentioned mathjax. Nothing is responsive, not even the cursor. Lasts about 10 seconds.

please record the message next time it appears, thanks!
 
  • #342
Greg Bernhardt said:
please record the message next time it appears, thanks!

It was only a couple seconds this time:

Loading [MathJax]/jax/output/HTML-CSS/jax.js

Happens when I open Random Thoughts.
 
  • #343
lisab said:
It was only a couple seconds this time:

Loading [MathJax]/jax/output/HTML-CSS/jax.js

Happens when I open Random Thoughts.

This may be one of those case when you're getting the fonts from MathJax and they are a bit slow. I loaded the STIX fonts into my Win 7 Fonts folder and Firefox is lightning fast. Might be worth a try; if it can be done in Chrome.
 
  • #344
I now get some sort of mathjax.js echo on a blank screen before the forum comes up.
 
  • #345
Now I am getting 504 errors. Although I think that is not some problem with PF.
 

Attachments

  • error.jpg
    error.jpg
    15.8 KB · Views: 420
Last edited:
  • #346
mishrashubham said:
Now I am getting 504 errors. Although I think that is not some problem with PF.

This is PF problem, from what I remember nginex was added to help deal with DDOS attack, since then it sometimes gives 502 and 504 errors, at least for me. I have never seen these errors before DDOS attack.

IMHO MathJax problems are unrelated and appear when MathJax servers are not fast enough. Unfortunately Opera seems to deal incorrectly with such situations
 
  • #347
DaveC426913 said:
I now get some sort of mathjax.js echo on a blank screen before the forum comes up.

can you elaborate? what are you doing when this happens? does it happen all the time?
 
Last edited:
  • #348
It happens anytime you enter a thread, sometimes it goes so quickly that you really have to be looking for it to see it. This is the message.

www.physicsforums.com/clientscript/mjsettings.js[/URL]

I started noticing it last week. I saw that you were discusing the issue Greg, or at least I thought that was what you were discussing. I'll pm you.
 
Last edited by a moderator:
  • #349
MathJax is dependent on the Amazon CloudFront so there is little they can do in terms configuring that. One developer asked if anyone here would be willing to install a plugin that would collect data that would be useful in troubleshooting the loading problems. PM me if interested.
 
  • #350
Code: 
borek@invincible ~ $ ./checkPF
PING physicsforums.com (74.86.200.109) 56(84) bytes of data.

--- physicsforums.com ping statistics ---
10 packets transmitted, 0 received, 100% packet loss, time 8998ms

traceroute to physicsforums.com (74.86.200.109), 15 hops max, 40 byte packets
 1  192.168.0.7 (192.168.0.7)  0.606 ms  0.568 ms  0.524 ms
 2  10.0.0.138 (10.0.0.138)  1.064 ms  0.990 ms  0.950 ms
 3  * * *
 4  xxxxx.tpnet.pl (xx.xx.xx.xx)  23.406 ms  23.614 ms  25.603 ms
 5  hbg-b2-link.telia.net (213.248.89.93)  40.144 ms  40.535 ms  40.570 ms
 6  hbg-bb2-link.telia.net (80.91.251.81)  46.344 ms  40.094 ms  39.173 ms
 7  nyk-bb2-link.telia.net (80.91.247.123)  125.381 ms nyk-bb2-link.telia.net (80.91.247.125)  123.475 ms  124.499 ms
 8  dls-bb1-link.telia.net (213.155.130.67)  165.859 ms dls-bb1-link.telia.net (213.155.130.209)  164.422 ms  165.928 ms
 9  te3-3.bbr02.eq01.dal01.networklayer.com (213.248.102.174)  169.799 ms  170.488 ms  170.192 ms
10  po6.dar02.sr01.dal01.networklayer.com (173.192.18.213)  170.019 ms  170.199 ms  170.734 ms
11  po2.fcr03.sr04.dal01.networklayer.com (66.228.118.190)  171.852 ms *  170.112 ms
12  * * *
13  * * *
14  * * *
15  * * *

For over two hours I was cut off (starting around 21:32 my time). And it had nothing to do with yesterdays situation :wink:
 
  • #351
Again, my IP seems to be blocked, I can use some random free proxy to connect to PF, but for some reason server doesn't like my current address. Previous post was from the IP assigned by my ISP, the one that is blocked. Pings don't pass through. Seems like nobody else has problems.

I wonder if I am not blocked because some of IPs in my range are blacklisted? They are assigned dynamically once per 24h, so blocking them doesn't make much sense.

I will try to reset modem, perhaps I will get a new IP this way.
 
  • #352
Resetting modem helped, so there is no doubt it is IP related.
 
  • #353
Borek said:
Resetting modem helped, so there is no doubt it is IP related.

Did you get a different IP?
Because usually you get a "lease", meaning you'll get the same IP until the lease expires.
 
  • #354
I like Serena said:
Did you get a different IP?
Because usually you get a "lease", meaning you'll get the same IP until the lease expires.

Completely different, 79.185.*.* vs 83.6.*.*.
 
  • #355
Borek said:
Resetting modem helped, so there is no doubt it is IP related.
Throws net over Borek.

Sit, stay!

Oh wait, this isn't chat.
 
  • #356
I like Serena said:
Did you get a different IP?
Because usually you get a "lease", meaning you'll get the same IP until the lease expires.

Borek said:
Completely different, 79.185.*.* vs 83.6.*.*.
If you have a dynamic IP address, you'll only keep that address until you disconnect from your ISP, the next time you log on, you will be given another IP address from you ISP. ILS, is that what you mean by a *lease*?
 
  • #357
Evo said:
Throws net over Borek.

Sit, stay!

Oh wait, this isn't chat.

:)

Evo said:
If you have a dynamic IP address, you'll only keep that address until you disconnect from your ISP, the next time you log on, you will be given another IP address from you ISP. ILS, is that what you mean by a *lease*?

I was just verifying that there was indeed an actual change in IP before assuming that the old IP was blocked.
It seemed unlikely that Borek wouldn't have checked, but sure is sure. :)

If you're interested, the concept of a lease in this context is for instance explained here:
http://en.wikipedia.org/wiki/Dynamic_Host_Configuration_Protocol"
 
Last edited by a moderator:
  • #358
I like Serena said:
:)



I was just verifying that there was indeed an actual change in IP before assuming that the old IP was blocked.
It seemed unlikely that Borek wouldn't have checked, but sure is sure. :)

If you're interested, the concept of a lease in this context is for instance explained here:
http://en.wikipedia.org/wiki/Dynamic_Host_Configuration_Protocol"
Ah, well I worked for AT&T that developed the internet for the US government. I worked on data networks from the early 70's. Never heard that term, we never used it. Someone posting on wikipedia wouldn't know that. <insert Aflac duck here> nah, nah. :-p

This must be a term that cropped up after the 70's. (Shows how old I am). :(
 
Last edited by a moderator:
  • #359
If, for some horrible, unfathomable reason, you are on Windows, maybe try:
Code: 
ipconfig \release
ipconfig \renew
?
 
  • #360
Evo said:
Ah, well I worked for AT&T that developed the internet for the US government.(

You must be smart!
 

Similar threads

PF Slow Again - Possible DDoS Attack?
  • · Replies 4 ·
Replies
4
Views
2K
Bug Slow Forum Apr 8: Limited Access, JS Error
  • · Replies 7 ·
Replies
7
Views
2K
Chemical Forums down, or how I learned what slowloris is
  • · Replies 8 ·
Replies
8
Views
1K
Complaint Possible Causes of Slow Response from PF and Solutions for Users and Staff
  • · Replies 22 ·
Replies
22
Views
5K
  • Sticky
Announcement Easy ways you can support Physics Forums
  • · Replies 97 ·
4
Replies
97
Views
50K
JavaScript PF Alert Machine: Can I Monitor Forum Alerts Without Logging In?
  • · Replies 3 ·
Replies
3
Views
1K
Could we make a practical solar fridge?
  • · Replies 30 ·
2
Replies
30
Views
4K
ABC reference frame synchronous generator modelling in Ltspice
  • · Replies 1 ·
Replies
1
Views
3K
11 reasons why you should be a Gold Member
  • · Replies 13 ·
Replies
13
Views
3K
Undergrad Lorentz Transformation: Premises + Derivation
  • · Replies 5 ·
Replies
5
Views
2K