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simpelmachines.org is slow

Started by lifeguard81, November 22, 2014, 04:36:33 AM

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LiroyvH

Quote
If the site went down, then the change to using google dns or open dns would not have worked.
If the site was down, it would have been down even after using one of them.
Trust me, I have dealt with this with 3 web hosts, and even my cable company had suggested using google dns to be able to access some sites that had dns updates. Now, how those that had been to the sites before were still able to access, would be only by the sites being cached.

No... You don't get it.

Ok, take this example:
random.doma.in is hosted on server A with IP 12.34.56.78. This is where it has been for a while and where you visit it.
Now the host changes the DNS of random.doma.in to Server B with IP 12.34.56.79 and takes the server A (12.34.56.78) offline.
The website is online perfectly fine at the new location (B), but is offline at the previous location (A).
Your ISP/computer still has server A (12.34.56.78) cached. Now you switch to OpenDNS. OpenDNS *does* know the new location and tells your computer it's now server B (12.34.56.79).
Result: you can visit the site again, switching to OpenDNS worked even whilst the site went down on the previous server.

You do understand there is a old and new location right...?
So the website can be offline at the old location, and online on the new location. So "it would have been down even after using one of them" is an incorrect conclusion, as "after using one of them" your DNS will have updated to the proper new location: and thus the site pops back up.

Is that an easier to understand explanation? :)
Trust me, I deal with DNS changes when moving websites on a daily basis...


Aso when the site is offline, visiting your cache is not truly visiting the website. Do a hard refresh, and sometimes already with a regular F5, and it'll state it cannot load it.


Quote
Now what has me worried a bit, is how many people are not able to access said sites, after such dns updates?
How would one know if their site is not accessible to others? Especially, if the person is already using google dns, or open dns, or a isp that does not have these dns issues. Makes me wonder how many people can't access SMF due to such things. (No, not saying that you changed dns, but as you know, some isp's especially cable companies, have lousy dns, themselves...LOL)

You can't tell how many people. It depends on a large variety of factors. Last visit, cache time of provider/computer, TTL of the DNS record, etc.
It's unpredictable how many people can't visit it.

How you know...? By asking. :P (Or if your site is popular: complaints. On social media, for example.)
Alternatively you could use downforeveryone, but that's unreliable when the site is merely offline pending a DNS update..

For your other scenario:
Using OpenDNS or Google's DNS servers constantly is no guarantee that you'll get faster updates actually... They also apply caches.
So even if you use OpenDNS: you can still run in to this issue. Easily.
... They do, however, have a tool for that to clear their cache: http://cachecheck.opendns.com/
Clear it there, clear cache on your computer: try again. (Note: some browsers may cache it on their own, restart those too.)
Voila.


... And considering nobody has problems accessing SMF due to a DNS issue/change: the amount is zero.
((U + C + I)x(10 − S)) / 20xAx1 / (1 − sin(F / 10))
President/CEO of Simple Machines - Server Manager
Please do not PM for support - anything else is usually OK.

Burke ♞ Knight

Well, downforeveryone is really not reliable, I agree to that...LOL
I know a site was down, as I had deleted the whole account, yet they still said it was up...
Also, they have stated sites as down, that I was able to load no issues.
One time, was even SMF here. Someone reported to me at my site that they could not get to SMF and downforeveryone stated it was down, but I could load, and see new posts on each test load, so I knew it was not cache I was seeing.

However, it seemed the person's issue was their own isp was doing line work, and their service was in and out. After they were done, he was able to load SMF and yet downforeveryone still reported it as down.

I never use downforeveryone anymore. I'll stick to other ways of seeing if a site is down or not.

LiroyvH

Quote
I know a site was down, as I had deleted the whole account, yet they still said it was up...

That's possible. If the DNS still pointed to the server, or downforeveryone (or one of their providers) had it cached: the server would have still responded. Not with the account as that was deleted, but with a default Apache or, for example, cPanel page.
To downforeveryone, that makes it look like it's online because it got a response.

Quote
Also, they have stated sites as down, that I was able to load no issues.
One time, was even SMF here. Someone reported to me at my site that they could not get to SMF and downforeveryone stated it was down, but I could load, and see new posts on each test load, so I knew it was not cache I was seeing.

That's possible, as we use multiple servers. So if the one downforeveryone and the person that reported it to you had gone down, but you're accessing the site through another server: you can see the site, they can't. And thus downforeveryone will report it is offline, as it doesn't check all the front-end servers; just the one it connects to at the time of the test.

Imho, downforeveryone is usually quite reliable. It's just a tool to make life easier, it can't do magic and always be right. :)
((U + C + I)x(10 − S)) / 20xAx1 / (1 − sin(F / 10))
President/CEO of Simple Machines - Server Manager
Please do not PM for support - anything else is usually OK.

Arantor

I'm seeing variously slow times.

Most pages are in the 1-2 seconds (server side, not client side) but I've seen a lot of 5-11 second times too with a few into the 20-second vicinity and one hitting 30 seconds. I'm also not using my iPad so it's not related to the ongoing hard-to-debug issue with that and the server firewall.

The only commonality I've seen thus far is that served by 134 tends to be the thing (the backend server has been 111, 113 and 114 with no appreciable difference between them)

Burke ♞ Knight

Couple refreshes of this page:

1.
Page created in 2.762 seconds with 24 queries.
Page served by: 10.0.100.135 (10.0.100.114)

2.
Page created in 0.912 seconds with 19 queries.
Page served by: 10.0.100.135 (10.0.100.134)

3.
Page created in 2.527 seconds with 19 queries.
Page served by: 10.0.100.135 (10.0.100.111)

4.
Page created in 3.003 seconds with 19 queries.
Page served by: 10.0.100.135 (10.0.100.112)

Arantor

I'm now off 135 myself, and seeing 1-2 second page load times.

Antes

Page created in 0.09 seconds with 18 queries.
Page served by: 10.0.100.135 (10.0.100.135)

Page created in 5.442 seconds with 25 queries.
Page served by: 10.0.100.135 (10.0.100.114)

Kindred

Page created in 0.08 seconds with 19 queries.
Page served by: 10.0.100.134 (10.0.100.135)

Page created in 0.211 seconds with 11 queries.
Page served by: 10.0.100.134 (10.0.100.112)

Page created in 0.555 seconds with 14 queries.
Page served by: 10.0.100.134 (10.0.100.135)
Слaва
Украинi

Please do not PM, IM or Email me with support questions.  You will get better and faster responses in the support boards.  Thank you.

"Loki is not evil, although he is certainly not a force for good. Loki is... complicated."

Arantor


Antes

Quote from: Arantor on November 24, 2014, 11:28:58 AM
Well aren't you just special? :P

He's surfing around fast as long as he doesn't get ban from servers :D :D

Kindred

ugh...

Page created in 5.367 seconds with 12 queries.
Page served by: 10.0.100.134 (10.0.100.112)

and yep... when I surf from home on my iPad, I frequently get banned from the server itself because of the iOS habit of leaving 80,000 connections open at once.
Слaва
Украинi

Please do not PM, IM or Email me with support questions.  You will get better and faster responses in the support boards.  Thank you.

"Loki is not evil, although he is certainly not a force for good. Loki is... complicated."

Arantor

I don't know why iOS does that, I really have to sit down with a debugger and packet sniffer sometime to figure out WTF is going on there.

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