vps interview questions
Top vps frequently asked interview questions
I just signed up with DreamHost VPS, and their sign-up process offered an unique IP address for an additional ~$4/mo.
I know what IP addresses are. Why would this uniqueness matter? Visitors are accessing my website via URL addresses anyway.
Source: (StackOverflow)
I know that Xen is usually better than OpenVZ as the provider cannot oversell in Xen.
However, what is the difference between Xen PV, Xen KVM and HVM (I was going through this provider's specs? Which one is better for what purposes and why?
Edit:
For an end-user who will just be hosting websites, which is better? From efficiency or other point of view, is there any advantage of one over the other?
Source: (StackOverflow)
This is a Canonical Question about Cloud Hosting
When deploying my application to the Internet:
- Should I chose a dedicated server, cloud hosting or a VPS?
- What factors should I consider when choosing?
Source: (StackOverflow)
I'm setting up on my VPS a vsftpd, and i don't want users be allowed to leave they're ftp home directory. I'm using local_user ftp, not anonymous, so I added:
chroot_local_user=YES
I've read in a lot of forum post, that this is unsecure.
- Why is this unsecure?
- If this is unsecure because of using ssh to join to my VPS as well, then I could just lock out these users from sshd, right?
- Is there an other option for achiving this behaviour of vsftpd? ( I dont want to remove read permissions on all folder/files for "world" on my system )
Source: (StackOverflow)
I admin a handful of cloud-based (VPS) servers for the company I work for.
The servers are minimal ubuntu installs that run bits of LAMP stacks / inbound data collection (rsync). The data is large but not personal, financial or anything like that (ie not that interesting)
Clearly on here people are forever asking about configuring firewalls and such like.
I use a bunch of approaches to secure the servers, for example (but not restricted to)
- ssh on non standard ports; no password typing, only known ssh keys from known ips for login etc
- https, and restricted shells (rssh) generally only from known keys/ips
- servers are minimal, up to date and patched regularly
- use things like rkhunter, cfengine, lynis denyhosts etc for monitoring
I have extensive experience of unix sys admin. I'm confident I know what I'm doing in my setups. I configure /etc files. I have never felt a compelling need to install stuff like firewalls: iptables etc.
Put aside for a moment the issues of physical security of the VPS.
Q? I can't decide whether I am being naive or the incremental protection a fw might offer is worth the effort of learning / installing and the additional complexity (packages, config files, possible support etc) on the servers.
To date (touch wood) I've never had any problems with security but I am not complacent about it either.
Source: (StackOverflow)
I'm a small company on not much budget providing websites and databases for charity and not-for-profit clients.
I have a few Debian Linux VPS servers and ensure I have daily backups to a different VPS than the one the service is hosted on.
Recently one of my hosting companies told me two drives failed simultaneously and so that data was lost forever. Stuff happens, they said sorry, what else could they do? But it made me wonder about cost-effective ways to basically get a VPS up again in the event of a hardware or other host-related failure.
Currently I would have to
- Spin up a new VPS
- Get the last day's backup (which includes databases, web root and website-specific config) over onto the VPS, and configure it like the last one etc.
- Update DNS and wait for it to propagate.
It would probably take a day or so achieve this, with the DNS propagation being a big unknown, although I have the TTL set quite low (hour or so).
Some hosts provide snapshots which can be used to replicate a set up to a new VPS, but there's still the IP and this doesn't help in the case that the host company cancels/suspends an account outright (I've been reading about this behaviour from certain hosting providers and it's scared me! I'm not doing anything spammy/dodgy and keep a close eye on security, but I realise that they literally have the power to do this and I'm quite risk averse).
Is this, combined with choosing reputable hosts, the best I can do without going for an incredibly expensive solution?
Source: (StackOverflow)
This question already has an answer here:
My VPS display this with df -h
Filesystem Size Used Avail Use% Mounted on
/dev/simfs 100G 46G 0 100% /
Does anyone have a idea to fix this ?
Source: (StackOverflow)
This question already has an answer here:
When renting a dedicated server, how can one be certain than he/she is not getting a VPS or some other virtual machine variant instead of a true dedicated hardware box?
Which checks can be run (assuming it is a linux box) to detect such case?
Source: (StackOverflow)
I am upgrading my shared hosting to VPS hosting, mainly to just add server administration skills to my development skills, so I'm facing a lot of new choices just signing up.
I need to choose a virtualization platform, either Xen or OpenVZ.
From what I can tell, OpenVZ is more "user-friendly", but other than that I can't really tell a difference.
I'm going to choose Ubuntu Linux, just because I believe it is the most user friendly and very popular, and I assume both Xen and OpenVZ work equally well with it.
For my purposes of "learning how to administrate a server" which do you think would be more appropriate, Xen or OpenVZ?
Source: (StackOverflow)
I'm relatively new to web development, so please be patient.
I'm primarily an iPhone developer, but have recently done a site for someone else using shared hosting. I could write to files in PHP on that site fine, without having to think about permissions.
I'm in the process of deploying a web service for a new app I'm making, but it's not really going smoothly. The most important difference here is I'm using someone else's server, and just have FTP/DB access.
Basically, I have a load of PHP files which make up my CMS, like so:
mysite.com/admin/manage_news.php
mysite.com/admin/manage_events.php
Those scripts then either edit the database, or files. They can interact with the DB fine, however, my scripts cannot write to the filesystem. They might, for example, attempt to write to the following files:
mysite.com/data/img/event_1.png
mysite.com/data/somefile.txt
This worked fine on my MAMP install (locally), but once deployed to the server, PHP spewed out errors everytime a write was attempted... something like this:
Could not open file "../data/img/someimage.png" for writing.
So I emailed the guy who's running the server, and he came back saying:
Does it work with public permission? (777)
And, it did - but I was very cautious with using public permissions, so disabled it straight away again. I emailed him saying "how can I make my PHP scripts write using standard user permissions", and he said:
Leave it as public, it'll be fine
I reckon it's an ip conflict somewhere in the domain resolution, but I'm not worried about it.
I then emailed him saying "surely this is insecure" or something along those lines, and he replied with the following:
the reality is that there are millions of website, including several that I manage that have 777 on various folders, it's just a way of life.
Could anyone give me some idea of a solution I could give him? Or what I can do to avoid having to use 777? I really don't like the idea of any folders on my site/service to be publicly writeable.
I would very much appreciate your advice as I know very little about web servers.
Source: (StackOverflow)
Does anyone have a ballpark figure of how much VPS ram (without burstable) I would need to have apache with wordpress and subversion as well as the MySQL instance?
Apache would host a couple of sites and SSL. MySQL would have just the Wordpress database. These sites are low traffic, less than 1k hits a day.
Source: (StackOverflow)
Currently I have a Hyper-v VPS with 2 (vCPU) processor. I would like to install SQL Server Express 2012 that has a limitation of 1 Socket or 4 Cores, whichever the lesser.
My Question: Are vCPU's counted as a single core, or as sockets? or something completely different?
Source: (StackOverflow)
I rented a small VPS (~130MB of RAM) to run an IRC bot. The bot is no longer needed so I have a VPS until the billing period ends.
I also have shared web hosting but can anyone think of what a VPS might be useful for that can't be done on shared hosting?
I'm a developer for both web and desktop apps.
Suggestions for larger VPS's also welcome.
Source: (StackOverflow)