startEc2InstanceSsh.R

#! /usr/bin/env Rscript

#start an instance
startup <- system("ec2-run-instances ami-b232d0db -k ec2ApiTools", intern=T)
Sys.sleep(45) #rather random but 45 seconds is typically long enough to boot

#query running instances
instances <- system("ec2-describe-instances", intern=T)
instancesParsed <- sapply(instances, strsplit, "\t")

runningInstances <- NULL
ri <- 1
latestStart <- strptime("1900-01-01T00:00:00", "%Y-%m-%dT%H:%M:%S")

for (i in 1:length(instancesParsed)){
  if (instancesParsed[[i]][[1]]=="INSTANCE") {
    if (instancesParsed[[i]][[6]]=="running") {
       runningInstances[[ri]] <- instancesParsed[[i]]
       startTime <- strptime(runningInstances[[ri]][[11]], "%Y-%m-%dT%H:%M:%S")
       if (startTime > latestStart) {
         latestStart <- startTime
         latestIndex <- ri
       }
       ri <- ri + 1
    }
  }
}

#return the DNS name of the running instance that was started last
dnsName <- runningInstances[[latestIndex]][[4]]
print(dnsName)

#fire up the SSH connection
system(paste("xterm -hold -e ssh -i ~/Documents/AWS/ec2ApiTools_rsa_id -D 9999 -o StrictHostKeyChecking=no root@", dnsName, sep=""), wait=F )