22 replies to this topic

[DianeV]

(As Ron knows), we're looking at moving our sites to a dedicated server.

Now, my experience is that separate IPs can be beneficial for SEO purposes, as well as other server purposes. In particular, different C-block IPs on different servers.

My question is whether separate IPs on the same server would have the same effect. Anyone have any experience with this?

[Jill]

It's only beneficial to have those things if you're a spammer. The rest of us don't need to care, imo.

[mcanerin]

Yup - from an internet viewpoint, each IP might as well be on a different server - there is no practical way (or real reason) to tell if it's on the same server or not.

Many websites run on server arrays (like Google) where many servers are connected together and act as one big server - no problem, and one of the reasons it isn't tracked.

Generally, different C Blocks are given to different providers, so in order to get 2 different C Block addresses on your computer you either have to get them both from a provider who in turn has at least 2 providers (which is common for good ISPs) or you have 2 providers going to your website. That would require one NIC for each provider, and is the only time, in practice, that having 2 different IPs has any effect whatsoever on your hardware.

It sounds like you have one provider giving you 2 IPs. No problem, and no worries

Ian

[mcanerin]

For the record, I do prefer to have at least 2 providers to my webserver (not 2 IP's from one provider, 2 providers) because I HATE it when my internet connection goes down, even for a moment.

Ian

[Michael Martinez]

If you send out email from your domains, having separate IP addresses in separate C-blocks is a good thing. Other than that, I agree that separate IP addresses is overkill for most people who operate multiple domains on one box.

The email issue is due solely, strictly to how email anti-spam systems work. If you get blacklisted for any reason, you can switch your mail domain over quickly until you resolve the problem.

I vet all IP addresses in advance before accepting them.

If you go with a large hosting provider, they can give you the separate C-blocks, but you may have to make a business case for it. They tend to be leery of that kind of request. I had to explain my blacklisting problems in detail the last time I changed providers.

[DianeV]

from an internet viewpoint, each IP might as well be on a different server - there is no practical way (or real reason) to tell if it's on the same server or not.

Thanks, Ian, that's what I wanted to know.

And thanks, Michael. That's another issue. Are you running the IPs through one of the spam DBs?

Lastly, Jill -- with all due respect, I don't think you're correct that nobody but spammers needs to care about these things. First of all, take a look at my portfolio; not a spammer among them, and there never will be.

Thing is, I've seen server logs for the "main" site on a shared IP sometimes logging pages from the other sites on that IP. I'm not quite sure how this happens, but it's entirely possible that the server got too busy and requests were shunted to the "main" site; if so, that then gives an inadvertent duplicate page scenario. I've had a client on a shared IP (mine) buy a second domain and point it at the IP without telling me ... and it then led to my site. Had I not read the server logs, I wouldn't have known this.

Given these and other issues, I don't see any reason to omit taking steps to ensure a proper, professional hosting environment. Given the fact that as time goes on, the number of optimized sites will continue to increase as they have in the last five or so years, waving away as unnecessary any opportunities to assist would not seem to be the best path to pursue. Yeah, it's technical, but so are lots of things -- but attention to details, IMO, is worth it.

Edited by DianeV, 01 October 2005 - 10:19 AM.

[Michael Martinez]

And thanks, Michael.  That's another issue.  Are you running the IPs through one of the spam DBs?

Yes, although I found out recently that even doing that isn't enough. My mail server got blacklisted twice a couple of weeks ago because the hosting provider installed qmail without customizing the configuration. I had to join the qmail discussion group to find out that it's highly exploitable in its default configuration (which is why I was blacklisted -- spammers found my server and used it as a relay).

So, if you're sending email from your server, don't stop with checking the IP addresses. Make sure your email software is set up properly. Qmail users need to make sure their control/me or control/helo files say "mail.{domain.name}" and not the default "localmail.localhost".

Thing is, I've seen server logs for the "main" site on a shared IP sometimes logging pages from the other sites on that IP.  I'm not quite sure how this happens, but it's entirely possible that the server got too busy and requests were shunted to the "main" site;

It's an indication of file corruption due to server load.

Unique IP hosting is overhyped for paranoid reasons, in my opinion. Back when I started insisting on unique IP addresses, both Inktomi and Altavista were known to ban sites by IP address. I wanted to make sure I wasn't hanging around in "bad neighborhoods". On my last shared hosting server, I found out I could look at the NETSTAT reports and found I was sharing that server with some interesting sites (but the IP addresses were unique, so there was some protection).

Google doesn't seem to care about IP addresses, and Yahoo! may no longer care about them. I'm not sure about MSN and Ask. Haven't really looked at the issue from the SE perspective for a long time. My chief concern for IP uniqueness is the email.

[DianeV]

Whoof! Running servers is a hassle. But I do like the control they give you far better than I like shared hosting.

Thanks for the qmail info; that's good to file away for when it's needed.

> It's an indication of file corruption due to server load.

Are you saying the actual file is corrupted, or that due to server load it's just not being read right because it's not as "available" as it should be, or ...?

In any case, it looks like we're going to have to look at the dedicated server issue sooner rather than later. We've been using virtual private servers, and that gets expensive -- at least, our next move would be more expensive than a dedicated server.

However, I get a bit of the willies when thinking of running the whole server myself. <grin>

Thanks, Michael. It's good to see you "around".

[Ron Carnell]

Thing is, I've seen server logs for the "main" site on a shared IP sometimes logging pages from the other sites on that IP. I'm not quite sure how this happens, but it's entirely possible that the server got too busy and requests were shunted to the "main" site ...

Possible, I suppose, but not very likely. Your httpd.conf data is read only once, Diane, when Apache initially starts, and then held in memory. That's why, when you make changes to httpd.conf manually, you always need to restart Apache for them to take effect. If a server were too busy to find something stored directly in memory, I honestly think it would be too busy to avoid a crash.

Assuming the site is configured correctly in httpd.conf (if it wasn't correct or was missing, as you already discovered, the site would be routed to the main site *every* time, not just intermittently), the more likely cause is an errant user agent sending an incorrect Host header (say, domaim.com instead of domain.com) or failing to send one at all. Except in the case of a badly written spider or scraper, that should be pretty rare, I would think?

I think there ARE valid reasons to run IP-based hosting, but I don't believe SEO is one of them. Trying to avoid blacklists is an even worse reason, in my opinion. Why check out fifty IP addresses when you can check out one and be done with it?

FWIW, a c-block is comprised of only 256 related addresses, and even the smallest Mom and Pop hosting outfit is probably going to have several c-blocks available. Whether multiple c-blocks can be used on a single server, however, depends on the routing configuration in the NOC. To avoid unnecessary "chatter" on the lines, it's common to configure a router to only pass a range of IP addresses down any given line. Indeed, that's the main function of a router. Essentially, that means the servers on that line hear only a subset of the total broadcasts coming into the NOC. Obviously, a c-block that doesn't fall within a router's configured range will never get to the servers down that line and can't be used. I have two dedicated boxes with one company in Florida, for example, that can use only one c-block each because that's the way the subnet is configured. If I needed more, they'd either have to reconfigure the router or move me to a different, larger subnet. My third server, on the other hand, is already running with two very different c-blocks. (Hint, Diane: Order additional IP addresses only after your new server is up, running, and fully tested. Chances are the additional IP's won't be contiguous with the ones that came with the box.)

[Jill]

I think different IPs and different cblocks is a completely different issue. I agree that sometimes you want your own IP address. I do have my highrankings.com site on a different IP address and then all the other sites on a shared IP. Years ago I used to make sure all sites had their own IP, but these days it just doesn't seem to be necessary.

But I stand by my earlier comment that you don't need separate cblocks unless you're attempting to portray sites as unrelated which actually are related. (In other words, trying to trick the search engines into believing that.)

[DianeV]

Yup, you're right, Jill, re c-block versus IP. Most of the sites are not related; arguably, my site and my developedtraffic blog are. Though I have to say that I don't see that there's anything inherently wrong with giving sites their own IPs, whether c-block related or not. I'm not inclined to set up a server to compensate for search engine failings rather than in a way that I see as proper or best.

It's enough -- this is a rant and not aimed at you, Jill -- it's enough that we have to spend time, however little, redirecting www to non-www or vice-versa; as a web designer, that time gets added to every site I do. Then there are the issues of what links they like; what links they don't like; how we have to design and build sites because SEs still can't read various standard old Web file formats (e.g., images, Flash, Javascript) even though they have vastly greater resources at their disposal to solve their problems than do I. Though this is a designer/developer rant, tell me it wouldn't make everyone's lives easier if SEs would just read text in images. I rather think they can but won't, and this one omission means that sites have to be designed differently than they could be just to cover SE failings. It also means that SEs have a harder time determining what a page is about because they fail to read intrinsic elements on the page. Read them already!

But ... back to the topic at hand.

Ron: so, thanks for the Apache/httpd.conf data.

- I'm wondering whether, on a dedicated server with multiple IPs, there is a .conf for each IP?

- Can a dedicated server have multiple SSL certificates ... one for each IP that needs it? Or would these need to be set up as VPSes (which sounds like a real drag to set up).

So many questions. I'm guessing I'm just going to have to get in there to find out, and am assuming there will be a learning curve. Unfortunately, there are a number of databases involved; moving those will hopefully not be too much trouble. <wince> But, luckily, I have access to the mySQL directories, I may be able to simply FTP the DBs from one server to another (I did this before successfully).

[Randy]

- I'm wondering whether, on a dedicated server with multiple IPs, there is a .conf for each IP?

It depends a bit upon what software is being used on the panel Diane. Typically all of the IPs all going to be listed in a single master httpd.conf file, however most control panels these days have a separate file --whether it's actually named httpd.conf or not-- that controls the configuration for each specific domain. Even if it's on a shared IP this is pretty much the way it is these days.

- Can a dedicated server have multiple SSL certificates ... one for each IP that needs it? Or would these need to be set up as VPSes (which sounds like a real drag to set up).

Yes a dedicated box can have multiple SSL certificates. Then you simply(?) tie the cert to whatever IP number you need it to respond to. I've got some dedicated boxes that have upwards of 50 or so SSL certs installed for various domains that need one. So no issue there.

[DianeV]

Okay re the .conf file(s). And the SSL certs. This is sounding ... exciting!

Wow. Control panel, eh? This might be a lot easier than I'm used to. I'm used to hand-coding the httpd.conf (there's a utility at Verio that helps you set it up, but hand-coding controls it better, IMO). I used to set up new users and sites via SSH ... or was that before SSH? Telnet, then. Being fussy with server logs, I even wrote some cron scripts that Verio put on its site. I do pretty well, but a server guru I'm not.

... which is well illustrated by this: Verio came out with a new line of VPSes that were "more like a native *nix install". Along with a semi-developed (at the time) control panel. Somewhere in there, I got myself all twisted up in user permissions -- to the point where I finally begged off, something I don't normally do. Which is what has made me wary of going to a dedicated server. I figure I'll probably have to deal with the permissions thing again, but if it's easier or just a tad more intuitive, I figure I can probably live through the experience this time. <hope springs eternal. lol> <never quit, and all that>

I *gotta* see one of these control panels. Then I can just do something, and then FTP in to the server to see what was done and where.

This is starting to sound like a huge relief. Many thanks.

[Jill]

Diane,

I'd recommend getting your dedicated service pre-installed with CPanel and WHM (I think that's what it's called.)

You can also get Plesk instead which is what we have now. But I've generally liked the control you have with Cpanel installs better.

You'll find it super easy to manage your server with either of those.

[DianeV]

Thanks, Jill. Super-easy sounds great.

The host I've considering does have cPanel, and I'll find out about WHM (WebHost Manager, according to cPanel's site).

And thanks for the comments re Cpanel versus Plesk; the host offers that, as well, so it's good to have some feedback.

Excellent. Thanks. Now, I'll go find some questions to answer in return for all this great help!