Great Western Coffee Shop

Sideshoots - associated subjects => News, Help and Assistance => Topic started by: grahame on January 24, 2015, 09:01:48



Title: DNS update - you may lose coffee shop while transfers happen and percolate
Post by: grahame on January 24, 2015, 09:01:48
You, dear users, know this site as "the Coffee Shop" at www.firstgreatwestern.info, but when you call up a page your computer transforms the www.firstgreatwestern.info into 83.170.95.163. It looks it up on via a "name server" which is logically close to you, and which talks to other name servers.  The 83.170.95.163 thing (the IP4 address) is to some extent geographic - think of it being computer number 163 in district 95 of city 170 and country 83, whereas the name is something that we choose logically based on who we are, not where we live.  So it's like a forename surname and the lookup system is like enquiring "where does Graham Ellis work" and being told "48, Spa Road, Melksham, Wilts".  With that latter piece of information, you can pop around and see me - with just my name, you're left guessing where I might be.

One of the elements we're using in this name lookup is very long in the tooth, and I'm re-arranging things so that we're more efficient for the future, and can retire one of the elements which is well past its "use by" date.  And this may mean a hiccough in the name lookup.  You might think that with "electronic speed" I could do this without you noticing, but the information about these name to IP mappings gets cached (stored) in order to keep the enquiry volume to a managable level, and even on central servers things are only updated every "so often".   So when I do the re-arrangement, it's possible that you'll find the coffee shop disappearing from your view for a while - with the worst case of "a while" being as much as a day or two.

Status update (via a name that won't be moved) - http://www.wellho.net/share/status.html

Change planned for overnight tonight (Saturday / Sunday) after you've had a chance to read this.


Title: Re: DNS update - you may loose coffee shop while transfers happen and percolate
Post by: ellendune on January 24, 2015, 09:16:08
So can you post a direct link to the new IP address in the status page to tide us over?



Title: Re: DNS update - you may loose coffee shop while transfers happen and percolate
Post by: grahame on January 24, 2015, 09:27:15
So can you post a direct link to the new IP address in the status page to tide us over?

The IP address of the Coffee Shop server will remain unchanged - 83.170.95.163 - and I will post that on the status page.  However, we use virtual hosting, so visiting 83.170.95.163 directly won't do much for you; techies might like to set up local resolution of 83.170.95.163 to www.firstgreatwestern.info .

This will probably go seamlessly through for most people.  But as an IT person, words like "probably" and "most" are ones I don't want to use.


Title: Re: DNS update - you may loose coffee shop while transfers happen and percolate
Post by: grahame on January 25, 2015, 01:55:12
As you will have gathered I've been doing a whole load of background work on the server and (investigating) a bit of a problem in the late evening - I've rolled the databases back by three hours and I'm re-checking things at the moment.  I have also moved the server DNS.

My apologies for the data loss - a couple of comments on these update threads, and (I think) a fining issue that Chris picked up, and a follow up "behind the counter".  I mention those here 'for the record'

As  write awaiting the next auto-backup .. and will see how it goes


Title: Re: DNS update - you may loose coffee shop while transfers happen and percolate
Post by: grahame on April 02, 2017, 18:57:11
I'll be moving the DNS server again - a further consolidation - at some time in the next few weeks.  The changes just over 2 years ago (see up-thread) shifted the name service onto a package that includes a dedicated host of 2012 vintage, and I'll be moving everything associated with that host onto a new virtual host which will mean that my pocked doesn't need to be quite so deep in the future.

Should be seamless for just about everyone as I'll set the DNS name timeout down to an hour well prior to the changeover, and change in the early hours - but warning you just in case you wake up in need of a coffee and find that it's still not percolated through one morning!


Title: Re: DNS update - you may loose coffee shop while transfers happen and percolate
Post by: Chris from Nailsea on April 02, 2017, 22:00:25
Thank you for that advance warning of those 'significant engineering works' here on the Coffee Shop forum, grahame.  ;)



Title: Re: DNS update - you may lose coffee shop while transfers happen and percolate
Post by: TonyK on April 02, 2017, 22:50:26
Let's hope that we lose nothing.


Title: Re: DNS update - you may loose coffee shop while transfers happen and percolate
Post by: grahame on April 05, 2017, 11:17:46
Transfer under way ...


Title: Re: DNS update - you may loose coffee shop while transfers happen and percolate
Post by: patch38 on April 05, 2017, 11:31:36
I have to say - that's the best explanation of IP addresses that I've ever read...  :)


Title: Re: DNS update - you may loose coffee shop while transfers happen and percolate
Post by: JayMac on April 05, 2017, 13:03:35
Transfer under way ...

That explains the DNS message I got earlier.


Title: Re: DNS update - you may loose coffee shop while transfers happen and percolate
Post by: grahame on April 05, 2017, 13:58:17
Transfer under way ...

That explains the DNS message I got earlier.

Yep ... that slight gap between unplugging from one place and plugging into another wasn't quite as slight as it should have been. Result, though, will allow me to cease paying for an old machine that has become uncompetitive.



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