Bring your dog's favorite food with you while you travel. This is the best way to ensure your dog does not experience any upset stomachs while you are on your trip. Make sure to look for a container with a good, airtight seal. And don't forget your dog will need easy access to water as well.
If you are traveling by RV, your best bet will be an elevated container that holds the dog food under the dish. These come with a bowl for water and another bowl for their food.
For people who like to camp or hunt with their dogs, the Vittles Vault SoftStore is very convenient. While keeping the container airtight, it also collapses as the food depletes. This and the fact that it is not hard-sided make it much easier to bring along.