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I assume this a sudden drop as you stated but sudden needs to be well defined. What can you tell me about it?
Option 1) >>> We were getting traffic in normal volume yesterday but it trickled down to zero in the span of a day.
Option 2) >>> It went down in an hour.
Here are the following steps to root-cause of the issue. (Both)
1) Check if any DNS updates were done incorrectly, causing the traffic to route to the wrong place. It takes some time for DNS to propagate slowly draining out the traffic.
2) There was a software update to the website and it is faulty & not handling the traffic. Since you are saying the traffic dropped, I assume it is the traffic to the site not coming but worthwhile analyzing issues with new software if any updates were done.
3) Firmware update to the Loadbalance in front of the web servers is another issue. It can be as simple as configuration update in LB causing it reroutes the traffic else ever.
4) The web servers are powered down accidentally.
Each of these above issues has a simple remedy when narrowed down to a single or multiple reasons.
Option 1) >>> We were getting traffic in normal volume yesterday but it trickled down to zero in the span of a day.
Option 2) >>> It went down in an hour.
Here are the following steps to root-cause of the issue. (Both)
1) Check if any DNS updates were done incorrectly, causing the traffic to route to the wrong place. It takes some time for DNS to propagate slowly draining out the traffic.
2) There was a software update to the website and it is faulty & not handling the traffic. Since you are saying the traffic dropped, I assume it is the traffic to the site not coming but worthwhile analyzing issues with new software if any updates were done.
3) Firmware update to the Loadbalance in front of the web servers is another issue. It can be as simple as configuration update in LB causing it reroutes the traffic else ever.
4) The web servers are powered down accidentally.
Each of these above issues has a simple remedy when narrowed down to a single or multiple reasons.
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Ok, when you say all of a sudden, do you mean to say that yesterday it was working fine and now it isn't? (yes).
And this isn't something we had expected meaning maybe some changes were intended to be made resulting in such drop to shift traffic to some other site. (crrect, this is not a behavior we want or had expected so this is a huge concern).
Alright, to understand the question a bit more, web traffic dropped overall or just from a specific device or OS type, mobile vs. desktop, etc.? (all of it).
Is this world wide or certain area of the world, country, region, etc. (worldwide).
Ok while I am sure I want to make sure of 1 more thing....when you say web traffic we aren't refering to those who are spending beyond x amount of time or signing up or placing a checkout, etc. but we are referring to people just not visiting the website so basically web vistor count has stopped incrementing. Correct? (yes)
Given this data, I think this is likely a very simple case and will likely jump to some end conclusions but if those are not true I can scale back and think through more details. (sure. what's on your mind?)
Well, do we know if:
1) we recently changed some dNS settings? Even if we fixed those it takes time to get the traffic re-routed correctly. (no)
2) we made some changes, enhancements, server changes, code changes, etc. (no)
Since this is a worldwide event, this doesn't make much sense. One other thing is, are we noticing this drop from a certain browser? I am thinking maybe it's related to that and that maybe I dont have a full scope / understanding of the problem yet. (correct. This has only been noticed for Chrome).
ok, so is it likely that the code we had isn't compatible with the new version of chorme and the older version of chorme is no longer supported? Wait, befoe you answer that Idon't think this is a valid case because if a older version of chrome worked with our code it will always work. It just won't support any new code enhancements that we might make and given we haven't made any code enhancemnets, this isn't a valid case. (yes, I am glad you re-thought through this).
ok, then the last think I can think of is that maybe our servers went down or are still down and we can tell by looking at the logs. Do you have any logs for us to look at? (yes, looknig at hte logs it seems that's the case).
Great! I would hence suggest for us to bring back our servers and see what happens. I still highly doubt that this will get the traffic back up 100% to the levels we expect since a worldwide company doesn't work on just 1 DC and hoenstly I am a bit surprised that the traffic wasn't picked up by secondary / backup DC. + Every part of the wrold and even region would use diff DC. So I still think this is not the core problem. Do you want me to explore other areas? (no that's fine. I got what I had wanted to evaluate. thank you).
ok great. So to close this out, I want to re-iterate that I didnt' analyze all the areas that I normally may think of such as competition, price strategy changes, etc because they didn't apply to this case. Also, while we did identify some cause of concern, I am 100% sure we haven't identified the core problem that will result in a 100% fix. We have chosen to not dig deeper.
Yes thank you.
And this isn't something we had expected meaning maybe some changes were intended to be made resulting in such drop to shift traffic to some other site. (crrect, this is not a behavior we want or had expected so this is a huge concern).
Alright, to understand the question a bit more, web traffic dropped overall or just from a specific device or OS type, mobile vs. desktop, etc.? (all of it).
Is this world wide or certain area of the world, country, region, etc. (worldwide).
Ok while I am sure I want to make sure of 1 more thing....when you say web traffic we aren't refering to those who are spending beyond x amount of time or signing up or placing a checkout, etc. but we are referring to people just not visiting the website so basically web vistor count has stopped incrementing. Correct? (yes)
Given this data, I think this is likely a very simple case and will likely jump to some end conclusions but if those are not true I can scale back and think through more details. (sure. what's on your mind?)
Well, do we know if:
1) we recently changed some dNS settings? Even if we fixed those it takes time to get the traffic re-routed correctly. (no)
2) we made some changes, enhancements, server changes, code changes, etc. (no)
Since this is a worldwide event, this doesn't make much sense. One other thing is, are we noticing this drop from a certain browser? I am thinking maybe it's related to that and that maybe I dont have a full scope / understanding of the problem yet. (correct. This has only been noticed for Chrome).
ok, so is it likely that the code we had isn't compatible with the new version of chorme and the older version of chorme is no longer supported? Wait, befoe you answer that Idon't think this is a valid case because if a older version of chrome worked with our code it will always work. It just won't support any new code enhancements that we might make and given we haven't made any code enhancemnets, this isn't a valid case. (yes, I am glad you re-thought through this).
ok, then the last think I can think of is that maybe our servers went down or are still down and we can tell by looking at the logs. Do you have any logs for us to look at? (yes, looknig at hte logs it seems that's the case).
Great! I would hence suggest for us to bring back our servers and see what happens. I still highly doubt that this will get the traffic back up 100% to the levels we expect since a worldwide company doesn't work on just 1 DC and hoenstly I am a bit surprised that the traffic wasn't picked up by secondary / backup DC. + Every part of the wrold and even region would use diff DC. So I still think this is not the core problem. Do you want me to explore other areas? (no that's fine. I got what I had wanted to evaluate. thank you).
ok great. So to close this out, I want to re-iterate that I didnt' analyze all the areas that I normally may think of such as competition, price strategy changes, etc because they didn't apply to this case. Also, while we did identify some cause of concern, I am 100% sure we haven't identified the core problem that will result in a 100% fix. We have chosen to not dig deeper.
Yes thank you.
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