Planning for a Data Centre Move
The plan has now changed. To keep costs down at this stage, there will be no development/backup server, so I have to move what I have to Fremont, with the Dallas one already being in a pre-production stage.
I don't see the move between data centres as taking too long - only 2.7Gb used, including the operating system.
Nevertheless, I need to make sure that the move involves as little downtime as possible.
I have changed the TTL of the DNS records for the domains hosted on that box as low as I can set them (20 minutes.)
Is there anything else I should do or know?
I will need this to happen at a pre-arranged time, so that I can do all the DNS changes and other stuff. Are you Linode guys able to do this? Wouldn't want to submit a ticket and have it happen just some time, as it might be the middle of the night for me and thus put the whole thing out of action for hours on end.
10 Replies
So any custom tasks could be done while your image travels.
At least I had it this way when I moved to Atlanta.
@anyone - is the IP address at the new DC known before the transfer?
Once that button is there, the machine you're moving to has been set, so your IP should be knowable. If it's not on the dashboard, the support folks should be able to tell you. And in any case, you don't actually migrate until you push that button.
More work for you but zero downtime. You'd pay for two servers only for a day or two.
However, I have to keep costs for my client minimised; whilst a day's worth of Linode is neither here nor there (wouldn't even buy a beer!) my time setting up the second server is another matter.
But thanks for the suggestion; it's something to which I had given consideration and, in other circumstances, might have gone with.
@smiffy:
However, I have to keep costs for my client minimised; whilst a day's worth of Linode is neither here nor there (wouldn't even buy a beer!) my time setting up the second server is another matter.
You don't have to set up a second Linode, just clone the one you already have (in the 'Settings and Utilities' menu).
After the move I noticed that some processes were inexplicably taking longer. The cause were wrong nameservers in /resolv.conf: the first two resolvers were still the old Atlanta resolvers, which apparently are configured to refuse queries from linodes in other data centres. This caused a small delay for every DNS resolution request until the 3rd fallback nameserver was used.
Putting in the correct resolver IPs fixed things.
If you have configured your linode to get all this info via DHCP you will not have this problem. In my case I had configured all network config statically. I did think of changing the IP addresses of my network interfaces for the move, but I forgot about DNS.
@pclissold:
@smiffy:However, I have to keep costs for my client minimised; whilst a day's worth of Linode is neither here nor there (wouldn't even buy a beer!) my time setting up the second server is another matter.
You don't have to set up a second Linode, just clone the one you already have (in the 'Settings and Utilities' menu).
Good point!