I had a problem on Google webmaster, I found there are 56 posts on my blog, but the default atom.xml that was recognized by Google webmaster only had 26 posts in it. It the same used for the rss feeds.
I wanted to submit all the posts to Google webmaster. Found these resources and wanted to share to those for whom this might help.
First we need to create a custom sitemap that will replace the default sitemap on blogger.
Step 1 - Create the Custom Sitemap:
Use this link, to generate the custom sitemap you will need, http://ctrlq.org/blogger/. make sure you enter your blog URL with http:// when you are submitting the link to generate the custom sitemap. Now you have the custom sitemap, copy the sitemap. It should look something like this:
# Blogger Sitemap generated on [Date]
Sitemap: http://[Blog URL]/atom.xml?redirect=false&start-index=1&max-results=500
Step 2 - Replace the custom sitemap:
From blogger, go to settings and search preference.
Now change "Enable custom robots.txt content?" to Yes. You now will see a text box. On the text box, paste the custom sitemap that you had copied.
Now save the changes.
Step 3 - Submit sitemap to Google webmaster:
Google will automatically crawl your new sitemap on the next run, still it is advisable to submit your new sitemap to google. For this login to Google webmaster tool.
Navigate to Optimization>>Sitemap
By default you will see "/atom.xml" listed on the sitemap. Now add the new sitemap that you had just created. Which should look like this
Click on Add/Test sitemap button on the top left. In the text box add the sitemap link without the base URL on it. It should be like this:
Test this URL. On successful test, again hit "Add/Test sitemap" and submit the sitemap this time. You will see your new sitemap listed on the list of sitemaps and also you will see a change in the number of links submitted.
With this you have done your part. Now google will take care of it during the next crawl and index all the posts/pages left out in the default /atom.xml.