:FM

:fe]`^li`e^KiXZbYXZbj`e;ilgXc C<8M@E>

8o\cK\`Z_dXee#=fkfc`X KI8:BJ Trackbacks offer a simple means for bloggers to connect

and share information. BY JAMES STANGER

trackback is a way for a blogger With trackbacks, two seemingly unre- Several content management systems to automatically notify different lated conversations become more (CMSs) include trackback options. In N8EKKFBEFN 8 blogs that he or she has either strongly associated. Each time an update Drupal [1], if you’ve enabled trackbacks, begun or extended a conversation with occurs in the conversation, the context a blogger on your system just has to another blogger. A trackback is one of becomes stronger and richer. Search en- enter the URL of a remote blogger who three main types of linkbacks (see the gines often rank pages higher if they are supports trackbacks, and the blogger N?8KÊJLGEwebsite has trackbacks enabled, one blogger can reach out to another on a separate site by sending a “ping” to that user. The ping simply says, “Here’s a topic that is related to what you’ve JL9J:I@9<KFC@ELO posted, check it out.” If a blogger on a separate site wants to D8>8Q@E<GI

22 ISSUE 94 SEPTEMBER 2008 NNN%C@ELO$D8>8Q@E<%:FD&E

included with Ubuntu 8.04. If you use a Once you’ve installed the module, are available in the Drupal Administer different CMS, the configuration will dif- you’ll need to enable it. To do this, go to section. Go to Administer | Settings | fer but the steps are similar. Administer | Modules, then scroll down Trackback, and you’ll find the menu through the list of installed modules. En- options shown in Figure 3. >\kk`e^JkXik\[ able the trackback module by selecting This menu allows you to determine To enable trackbacks in Drupal, you’ll the checkbox next to it (Figure 2), then exactly how Drupal will handle track- need the TrackBacks module, which is click on the Save configuration button. If backs. Settings include: available at the Drupal website [5]. you plan on using trackbacks along with ฀ Because so many implementations of blogging, you’ll also want to enable the ฀ Drupal exist, the creators have worked blogging module. ฀ ฀฀ hard to support both 5.x and 6.x ver- ฀ ฀ sions. As with most modules in Drupal, :fe]`^li`e^KiXZbYXZbj If you enable auto-detection in this par- installation of the module is simple. Sim- The official trackback documentation is ticular Drupal module, any URL you post ply untar and uncompress the archive rather sparse on the configuration topic will be checked automatically for a inside of the /var/www/drupal/modules/ [6]. Most of the configuration options trackback link. It doesn’t matter whether directory. Again, if you are using a differ- ent Linux version, substitute the correct Trackbacks and Linkbacks path for your particular distribution. A trackback is a particular form of a link- establishing a relationship. Once you’ve unpacked the module, back. Three methods of linkback exist: UÊ,ivL>VŽÊqÊ
˜Êˆ˜VÀi>Ș}ÞÊÀ>ÀiÊÌiÀ“Ê your /var/www/drupal/modules/ direc- UÊ*ˆ˜}L>VŽÊqÊ
ÊÃiÌʜvÊ«ÀœÌœVœÃÊÌ >ÌÊ>‡ describing a tracking protocol that al- tory should have the structure shown in lows you to determine quickly when a lows an author to determine the remote Figure 1. You shouldn’t have to restart remote site has linked to your content sites and authors who have generated Apache after installing the module. If or web page. You can also use ping- links to them. you are upgrading from a previous mod- backs to automatically generate reports. You can learn more about linkbacks in all ule version, however, you’ll have to go UÊ/À>VŽL>VŽÊqÊ-ˆ“ˆ>ÀÊ̜Ê>Ê«ˆ˜}L>VŽ]ÊLÕÌÊ Ì iˆÀÊvœÀ“Ãʈ˜ÊÛ>ÀˆœÕÃÊÜÕÀViÃ]Ê>Ì œÕ} Ê Administer | Modules then run the up- more prone to spamming because con- ÊÀiVœ““i˜`ÊLi}ˆ˜˜ˆ˜}Ê>ÌÊ7ˆŽˆ«i`ˆ>ÊQÓR]Ê date.php script. nections can be initiated without first then going to other sources [3] [4]. N8EKKFBEFN N?8KÊJLGE

JL9J:I@9<KFC@ELO D8>8Q@E<GI

NNN%C@ELO$D8>8Q@E<%:FD&E

you enter the link in a URL or plain text form. The trackback module will check each URL in your document, and it will check to see whether the URL on each page goes to a site that allows and ac- cepts trackbacks. If the remote site does allow trackbacks, the Drupal trackback module will send a ping to the trackback URL found on the remote page. Auto-detection of every URL can bog down your server, especially if you have quite a few URLs on your page. If you’re worried about the volume, use the Run auto-detection on cron option, which de- lays the URL check until the next time cron is run. If you set cron to run at a time when the server is not busy, it is possible that no one will notice the per- =`^li\)1:i\Xk`e^XYcf^^`e^\ekipfeZ\k_\kiXZbYXZbdf[lc\`j\eXYc\[% formance slowdown. The problem with this option is that you won’t have track- backs, other bloggers might have a prob- To allow trackbacks for these other backs enabled instantly. It’s up to you to lem initiating contexts and pings. content types, go to Administer | Settings configure your cron settings optimally. Trackback location determines where | Content types and you will see the vari- Also remember that auto-detection trackback replies will appear in a blog- ous choices. To enable trackbacks for all can open your server to spam track- ger’s post. The default setting positions new pages, click on configure next to the backs, a trackback that attempts to link the trackback URL immediately beneath content type, and choose Enabled under your content to unrelated postings. This the post, but you can have these entries Trackbacks. form of spam is as annoying as tradi- posted on a separate page or inline with These trackback settings are not retro- tional email spam. the text. Most administrators keep the active; if you enable trackbacks for new If you choose to moderate your track- default setting because most people pages, you will still have to go back and backs, you will have to manually con- want to see how popular the posting is re-publish existing pages to add track- sider each and every submission. If with other bloggers. If you want to hide backs to your previous work. This step you’re already busy as an administrator, trackback replies for whatever reason, will enable trackbacks for any older selecting the Moderation setting will select Display on a separate page. page, and you’ll have to do this for each make your life even busier. However, page individually. it does let you review the suitability of :fe]`^li`e^:fek\ekKpg\j If you want to enable trackbacks trackbacks and reduce the amount of The final configuration task is to deter- for individual entries, you will have trackback spam. To review trackbacks, mine which content types you want to select the Administer | Trackbacks menu enable for trackbacks. Trackbacks are How Do Trackbacks Work? option. enabled by default for all blogs in A trackback is an http packet sent be- Search engines and many bloggers Drupal, no matter what version you’re tween one web server and another. It is want to see only trackbacks that have using. However, they are the only con- sent whenever a user chooses to enable been mutually initiated. If you opt to tent type enabled by default. The user ˆÌ]ÊÕÃÕ>ÞÊÜ i˜ÊÌ iÊLœ}}iÀÊVÀi>ÌiÃʜÀÊ reject one-way trackbacks, then you re- must explicitly allow trackbacks for updates content. Trackbacks are imple- quire mutual trackbacks. Although you other content, such as pages, stories, mented with the use of either POST or might increase the quality of you track- or other types. GET queries. These queries are exactly the same as those used in processing HTML forms. Trackbacks were created with the use of existing queries to capi- Ì>ˆâiʜ˜Ê«ÀiۈœÕÃÊܜÀŽ]Ê>˜`Ê>ÃœÊLi‡ cause the developers didn’t want to create a new type of traffic that could be blocked easily by firewalls and other security software. -̈]ʈ̽ÃÊ«œÃÈLi]ÊÌ œÕ} Ê՘ˆŽiÞ]ÊvœÀÊ this type of traffic to be blocked. You might want to test to see whether your pings are going through to remote sys- Ìi“ðÊ/œÊÛiÀˆvÞÊ>Ê«ÀœLi“]ÊVœ˜Ãˆ`iÀÊÀi‡ viewing the Trackback Technical Specifi- =`^li\*18]`e`j_\[Ycf^\ekip#Zfdgc\k\n`k_XkiXZbYXZbLIC% cation [9].

24 ISSUE 94 SEPTEMBER 2008 Trackbacks in Drupal :FM

to explicitly enable them for each con- You can send a trackback to any track- ming. However, some groups have found tent type by clicking on each URL and back-enabled site; you aren’t limited to that trackbacks help increase their hit enabling the trackback feature. just Drupal or another CMS. WordPress ratio for Google and Yahoo! searches. and many other major blogging tools More importantly, trackbacks support :i\Xk`e^X9cf^wordpress-trackback-tutorial If I want to manually ping other sites trackback results. Another option is to [5] Drupal trackbacks page: http:// drupal. org/ project/ trackback that have trackbacks enabled, all I would install one of the common Drupal anti- [6] Trackbacks documentation: have to do is put in the URL of the blog- spam modules [7]. Additional modules http:// drupal. org/ handbook/ ging site that will receive the trackback. that can help you combat spam also are modules/ trackback A blogger at the other site will notice the available through Drupal [8]. [7] Drupal anti-spam module: ping I’ve just sent and will then be able http:// drupal. org/ project/ spam to choose whether or not to accept my :feZclj`fe [8] Spam control module: request for a trackback. Trackbacks aren’t going to make a blog- http:// drupal. org/ node/ 206787 Once I click the Submit button, my ger instantly popular, and they could [9] Trackback technical specification: blog entry will be shown with the track- cause additional work if you are serious http://www. sixapart. com/ pronet/ docs/ trackback_spec back URL. about reviewing URLs to thwart spam- 

   



 












  


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