I have been trying to apply some Magento patches via SSH (SUPEE-5344 and SUPEE-1533) from the Magento Community Edition download page (https://www.magentocommerce.com/products/downloads/magento/)

I am running in a SSH session:

sh PATCH_SUPEE-1533_EE_1.13.x_v1-2015-02-10-08-18-32.sh

but keep getting the following error:

Error! Some required system tools, that are utilized in this sh script, are not installed: Tool(s) "patch" is(are) missed, please install it(them).

I have tried applying earlier patches but receive the same error message. How do I resolve this to apply the patches?

Answer:

The solution is to install the patch package:

yum install patch

Then run sh the patch file:

sh PATCH_SUPEE-1533_EE_1.13.x_v1-2015-02-10-08-18-32.sh

Checking if patch can be applied/reverted successfully... Patch was applied/reverted successfully.

Repeat for all missing patches.

Note: I provided this as I spent quite a bit of time on this before realizing that the error being thrown wasn't for a previous patch but for the patch package itself.