Jenkins not executing jobs (pending - waiting for next executor)

In my case it was caused by number of executors (I had 1) and running Jenkins Job (Project) from Pipeline (my pipeline script started other Job in Jenkins). It caused deadlock - my pipeline held executor and was waiting for its job, but the job was waiting for free executor.

The solution may be increasing of # of executors in Jenkins -> Manage Jenkins -> Manage Nodes -> Configure (icon on required node).

The Jenkins admin console can run, even with the Master node offline. This can happen when Jenkins runs out of disk space.

To confirm, do the following (with thanks to geekride - jenkins-pending-waiting-for-next-available-executor):

• go to Jenkins -> Manage Jenkins -> Manage Nodes
• examine the "master" node to see if it is offline. It may be reporting that the master node is out of disk space.

In my case, I had the following set in my JenkinsFile

node('node'){ ... }

There was no node called 'node', only master (the value had been left in there after following some basic tutorials). Changing the value to 'master' got the build working.

• go to Jenkins -> Manage Jenkins -> Manage Nodes
• examine the "master" node.(Click on configure icon)

In my case No of executors was set to 0. Increased it and issue got fixed.