Site loading slow

praveen · July 24, 2010, 00:22

Today I find cfd-online pages take a long time to load. I am in India. Its actually been slow for last 2-3 days if I remember correctly, but today is still slower.

pete · July 24, 2010, 04:15

Are all parts of the site slow or only some sections?

praveen · July 24, 2010, 04:29

I have checked forums and wiki, and they are slow. Hitting "Post Reply" to a message also takes a long time to load.

pete · July 24, 2010, 06:23

The server is not very highly loaded right now. A few days ago the server was under quite some stress due to a massive spam bot attack, but that bot is gone for now.

If CFD-Wiki and the Forums are the only sections that are slow it could perhaps be related to our database engine (MySQL), since those sections make heavy use of MySQL. I'm currently on a mobile connection so for me eveyrything is quite slow now. Is, for example, the links section quick for you or is that also quite slow? The links section is mainly plain HTML pages so if that is also slow it must be a problem which is not directly related to our server.

niklas · July 26, 2010, 09:06

The last days cfd online has become incredibly slow, every page takes about 1 min to load for me.

praveen · July 26, 2010, 09:20

It was very slow just a few minutes back. But now it seems to be fine.

pete · July 26, 2010, 22:19

We have changed some settings in our firewall just now. Apparently our web-host had imposed more strict hacking filters so that we automatically banned IP ranges that had computers that the filter indicated were trying to hack our server. We have relaxed the filters slightly now.

These firewall filters could be related to the slowness problems also. Is it better now?

praveen · July 27, 2010, 11:20

Its again slow and practically unusable. Slow both from my office and home, which are different ISPs.

jola · July 27, 2010, 18:33

We are examining the network problems. Right now it is also very very slow for me, and then 10 minutes later it is quick again. We do not know why and our ISP is helping us to diagnose the problem.

jola · July 28, 2010, 04:47

We have had two different problems with www.cfd-online.com lately, one problem is related to our firewall and some unnecessary strict hacking filters and one problem is related to our Apache web-server installation and Apache stalling.

The firewall filters have caused automatic bans of IP ranges that we did not intend to ban. For example, a couple of universities have been banned automatically by our firewall because they have one student who has been trying his skills as a hacker... These filters have now been relaxed and we have received reports that the universities that got banned are now able to access CFD Online again.

The Apache web-server problems is what causes our site to become very very slow at times. We have not solved this problem yet. We can fix it temporarily by restarting Apache, but that is not a long-term solution. Hopefully we will soon find why Apache all of a sudden is breaking up for us.

We apologize for all these problems. These things always tend to happen when you are away on vacation

niklas · July 28, 2010, 07:33

Quote:

Originally Posted by jola

For example, a couple of universities have been banned automatically by our firewall because they have one student who has been trying his skills as a hacker...

we want names

now it is working properly again.

jola · July 29, 2010, 04:02

Is anyone still having problems with www.cfd-online.com being very very slow or delivering an incorrect frontpage (the Apache installation page)? If you do please post a quick reply here so that we know that the problem is not completely solved.

We have gone through our server installation with a fine comb and have fine-tuned several settings both on the Apache web-server and on several other tools that we use (DNS server, firewall, spam and hacking filters, mail-scanning, ...). We have not found anything that can explain why our web-server stalled and became virtually unusable earlier this week though. Now the web-server has been working well for 24 hours and we hope that all the things we changed will keep www.cfd-online.com quick and healthy.

However, it is a bit irritating that we haven't found a single root cause of these problems. Hence, they might come back an hunt us again.

praveen · July 29, 2010, 04:07

Seems fine to me now. I dont feel any slowness at present.

pete · July 30, 2010, 04:53

Site seems to still be working well. Please contact us if anyone is still having problems. Yesterday we had a lot of traffic and easily served more than 3,000 web-pages per hour for a long period (see http://www.cfd-online.com/Stats/#hourrep) and the server was not even half-loaded.

sail · March 6, 2011, 19:18

hi. just want to report that the forum is getting really slow (has been few days)

it need around 1 minute to give me any page, even if ti contains just one message.

i'm in the uk and this happens with various isp.

pete · March 7, 2011, 03:00

I have also noticed the site being a bit slow over the last week. Not as slow as you mention, but slower than before. It is not related to the server being overloaded and it is not related to only http traffic. Most likely it is a network issue. I will send a question to our ISP to ask if he has any ideas what might be causing this. Anyone else who has also noticed this slowness over the last week?

I should also say that since around Christmas cfd-online.com has been running with a throttled network speed. The reason is that our ISP was attacked by a hacker who managed to start up very aggressive IRC flood-bots. These bots crashed his entire network. Several servers were compromised and we think that the hosting environment our ISP runs has a security hole. While we are still running on this vulnerable hosting environment we will run with a throttled network speed. I do not think that this is what causes the slowness seen over the last week though. This mainly affects large file transfers.

We have started to move over to a completely new hosting environment. Soon we will be ready to move over the entire site to a completely reinstalled server with a new hosting environment. Then we will run full speed without any network throttling. If you want to follow the development on this please read our twitter page: http://www.twitter.com/cfdonline

akidess · March 8, 2011, 04:57

I have noticed the slowdown in the last days as well. Right now it's slow but tolerable; earlier this morning pages from cfd-online would take minutes to load.

jola · March 9, 2011, 14:31

Our ISP has changed something in our network configuration. Is the site quicker now or is it still slow?

akidess · March 9, 2011, 16:20

It seems to be a lot quicker now!

sail · March 9, 2011, 21:03

definitely lot better!

well done.

July 24, 2010, 00:22	Site loading slow	#1
praveen Super Moderator Praveen. C Join Date: Mar 2009 Location: Bangalore Posts: 342 Blog Entries: 6 Rep Power: 18	Today I find cfd-online pages take a long time to load. I am in India. Its actually been slow for last 2-3 days if I remember correctly, but today is still slower.

July 28, 2010, 04:47	Two server problems	#10
jola Administrator Jonas Larsson Join Date: Jan 2009 Location: Gothenburg, Sweden Posts: 824 Rep Power: 10	We have had two different problems with www.cfd-online.com lately, one problem is related to our firewall and some unnecessary strict hacking filters and one problem is related to our Apache web-server installation and Apache stalling. The firewall filters have caused automatic bans of IP ranges that we did not intend to ban. For example, a couple of universities have been banned automatically by our firewall because they have one student who has been trying his skills as a hacker... These filters have now been relaxed and we have received reports that the universities that got banned are now able to access CFD Online again. The Apache web-server problems is what causes our site to become very very slow at times. We have not solved this problem yet. We can fix it temporarily by restarting Apache, but that is not a long-term solution. Hopefully we will soon find why Apache all of a sudden is breaking up for us. We apologize for all these problems. These things always tend to happen when you are away on vacation

July 29, 2010, 04:02	Server has been working well for 24hours now	#12
jola Administrator Jonas Larsson Join Date: Jan 2009 Location: Gothenburg, Sweden Posts: 824 Rep Power: 10	Is anyone still having problems with www.cfd-online.com being very very slow or delivering an incorrect frontpage (the Apache installation page)? If you do please post a quick reply here so that we know that the problem is not completely solved. We have gone through our server installation with a fine comb and have fine-tuned several settings both on the Apache web-server and on several other tools that we use (DNS server, firewall, spam and hacking filters, mail-scanning, ...). We have not found anything that can explain why our web-server stalled and became virtually unusable earlier this week though. Now the web-server has been working well for 24 hours and we hope that all the things we changed will keep www.cfd-online.com quick and healthy. However, it is a bit irritating that we haven't found a single root cause of these problems. Hence, they might come back an hunt us again.

July 30, 2010, 04:53	Still working	#14
pete Administrator Peter Jones Join Date: Jan 2009 Posts: 682 Rep Power: 10	Site seems to still be working well. Please contact us if anyone is still having problems. Yesterday we had a lot of traffic and easily served more than 3,000 web-pages per hour for a long period (see http://www.cfd-online.com/Stats/#hourrep) and the server was not even half-loaded.

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July 24, 2010, 04:15		#2
pete Administrator Peter Jones Join Date: Jan 2009 Posts: 682 Rep Power: 10	Are all parts of the site slow or only some sections?

July 24, 2010, 04:29		#3
praveen Super Moderator Praveen. C Join Date: Mar 2009 Location: Bangalore Posts: 342 Blog Entries: 6 Rep Power: 18	I have checked forums and wiki, and they are slow. Hitting "Post Reply" to a message also takes a long time to load.

July 24, 2010, 06:23		#4
pete Administrator Peter Jones Join Date: Jan 2009 Posts: 682 Rep Power: 10	The server is not very highly loaded right now. A few days ago the server was under quite some stress due to a massive spam bot attack, but that bot is gone for now. If CFD-Wiki and the Forums are the only sections that are slow it could perhaps be related to our database engine (MySQL), since those sections make heavy use of MySQL. I'm currently on a mobile connection so for me eveyrything is quite slow now. Is, for example, the links section quick for you or is that also quite slow? The links section is mainly plain HTML pages so if that is also slow it must be a problem which is not directly related to our server.

July 26, 2010, 09:06		#5
niklas Super Moderator Niklas Nordin Join Date: Mar 2009 Location: Stockholm, Sweden Posts: 693 Rep Power: 29	The last days cfd online has become incredibly slow, every page takes about 1 min to load for me.

July 26, 2010, 09:20		#6
praveen Super Moderator Praveen. C Join Date: Mar 2009 Location: Bangalore Posts: 342 Blog Entries: 6 Rep Power: 18	It was very slow just a few minutes back. But now it seems to be fine.

July 26, 2010, 22:19		#7
pete Administrator Peter Jones Join Date: Jan 2009 Posts: 682 Rep Power: 10	We have changed some settings in our firewall just now. Apparently our web-host had imposed more strict hacking filters so that we automatically banned IP ranges that had computers that the filter indicated were trying to hack our server. We have relaxed the filters slightly now. These firewall filters could be related to the slowness problems also. Is it better now?

July 27, 2010, 11:20		#8
praveen Super Moderator Praveen. C Join Date: Mar 2009 Location: Bangalore Posts: 342 Blog Entries: 6 Rep Power: 18	Its again slow and practically unusable. Slow both from my office and home, which are different ISPs.

July 27, 2010, 18:33		#9
jola Administrator Jonas Larsson Join Date: Jan 2009 Location: Gothenburg, Sweden Posts: 824 Rep Power: 10	We are examining the network problems. Right now it is also very very slow for me, and then 10 minutes later it is quick again. We do not know why and our ISP is helping us to diagnose the problem.

July 29, 2010, 04:07		#13
praveen Super Moderator Praveen. C Join Date: Mar 2009 Location: Bangalore Posts: 342 Blog Entries: 6 Rep Power: 18	Seems fine to me now. I dont feel any slowness at present.

March 6, 2011, 19:18		#15
sail Senior Member Vieri Abolaffio Join Date: Jul 2010 Location: Always on the move. Posts: 308 Rep Power: 16	hi. just want to report that the forum is getting really slow (has been few days) it need around 1 minute to give me any page, even if ti contains just one message. i'm in the uk and this happens with various isp.

March 7, 2011, 03:00		#16
pete Administrator Peter Jones Join Date: Jan 2009 Posts: 682 Rep Power: 10	I have also noticed the site being a bit slow over the last week. Not as slow as you mention, but slower than before. It is not related to the server being overloaded and it is not related to only http traffic. Most likely it is a network issue. I will send a question to our ISP to ask if he has any ideas what might be causing this. Anyone else who has also noticed this slowness over the last week? I should also say that since around Christmas cfd-online.com has been running with a throttled network speed. The reason is that our ISP was attacked by a hacker who managed to start up very aggressive IRC flood-bots. These bots crashed his entire network. Several servers were compromised and we think that the hosting environment our ISP runs has a security hole. While we are still running on this vulnerable hosting environment we will run with a throttled network speed. I do not think that this is what causes the slowness seen over the last week though. This mainly affects large file transfers. We have started to move over to a completely new hosting environment. Soon we will be ready to move over the entire site to a completely reinstalled server with a new hosting environment. Then we will run full speed without any network throttling. If you want to follow the development on this please read our twitter page: http://www.twitter.com/cfdonline

March 8, 2011, 04:57		#17
akidess Senior Member Anton Kidess Join Date: May 2009 Location: Germany Posts: 1,377 Rep Power: 29	I have noticed the slowdown in the last days as well. Right now it's slow but tolerable; earlier this morning pages from cfd-online would take minutes to load.

March 9, 2011, 14:31		#18
jola Administrator Jonas Larsson Join Date: Jan 2009 Location: Gothenburg, Sweden Posts: 824 Rep Power: 10	Our ISP has changed something in our network configuration. Is the site quicker now or is it still slow?

March 9, 2011, 16:20		#19
akidess Senior Member Anton Kidess Join Date: May 2009 Location: Germany Posts: 1,377 Rep Power: 29	It seems to be a lot quicker now!

March 9, 2011, 21:03		#20
sail Senior Member Vieri Abolaffio Join Date: Jul 2010 Location: Always on the move. Posts: 308 Rep Power: 16	definitely lot better! well done.