Should I block competitor?

[Jez123]

One of my competitors is frequently all over my site. He used to continually click adwords ads until I excluded his IP (and reported him to Google). Should I go the whole distance and ban his IP from my site?

I don't trust him at all - since he has been visiting my site regularly I have had thousands of hack attempts on the wordpress admin login pages (luckily I have a plugin that suspends IP's for 48 hours for 4 incorrect login attempts). I can't prove anything, obviously, but he is certainly up to no good.

Should I block him? If so, how best to do it?

[engine]

They have no legitimate purpose to attempt such log ins. Block the IP, no matter who it is.

Block them with .htaccess
[webmasterworld.com...]

[Swanny007]

Absolutely, yes, block them in .htaccess so they see nothing.

[phranque]

something to consider when blocking a live human - if you use a Deny or a mod_rewrite [F] flag to block a request, you are sending a 403 Forbidden response, which can have psychological effects.
if your blocking technique uses mod_rewrite, you also have the option of using the [G] flag which sends a 410 Gone response.
it's a subtle thing, but one message is about the visitor and the other message is about the content.

[Hoople]

Redirect him to his own site <EG>

[lucy24]

which can have psychological effects

Paradoxically, you only say this because you're a webmaster. Until I had my own site with its own htaccess, I didn't really understand what a 403 [F] is. There are two things a human sees:
404 = ain't no such page
403 = this directory doesn't have an index
In practice, that is the only time a human ever sees a 403 page. So you may not even realize that you've been unconditionally blocked. My current 403 page-- written entirely for humans-- says
::shuffling papers::

I don’t know how you got here, so you’ll have to use your browser’s Back button to return.

If you don’t know how you got here, these are the general areas to try. {the page includes the ordinary navigation footer} If you got here by clicking on a link from elsewhere on this site, please contact the webmaster {my contact page is open to everyone} so I can fix it.

Finally: If you clicked on one of the links below and got bounced right back here, it means the server thinks you are a robot. Again, contact me and I’ll see what I can do.

[Jez123]

Thanks everyone. That's helpful. Any tips on how I would implement the 410 option?

[lucy24]

A 410 never happens automatically, so you have to code it explicitly. You mentioned wordpress. Do you use htaccess?

It's clear that you already know when it's your competitor visiting. So that's what you block, whether it's his IP address or a distinctive UA or something else.

For example

RewriteCond %{REMOTE_ADDR} ^12\.23\.56\.78$
RewriteRule (^|/|\.html)$ - [G]

replacing "\.html" with any extensions you actually use for pages. The sole reason for the (^|/|\.html)$ element is to keep the server from having to stop and evaluate the condition on every single request. Presumably your evil competitor is not drifting around making "cold" requests for images and stylesheets.

If you currently don't have any other 410s, you may also like to make a custom 410 page that says something like "Get a life!"