Draft DNS resolve speed preview script for Linux for quick troubleshoot DNS resolve speed issues
#!/bin/bash DOMAINS="ibm.com yahoo.com google.com oracle.com bmw.com audi.com cnn.com bbc.com dw.com wikipedia.org mit.edu" for domain in $DOMAINS; do echo $domain dig $domain |grep Query done
Example execution
time ./dns_bench.sh
Example output
ibm.com ;; Query time: 32 msec yahoo.com ;; Query time: 1 msec google.com ;; Query time: 2 msec oracle.com ;; Query time: 31 msec bmw.com ;; Query time: 34 msec audi.com ;; Query time: 122 msec cnn.com ;; Query time: 31 msec bbc.com ;; Query time: 36 msec dw.com ;; Query time: 36 msec wikipedia.org ;; Query time: 1 msec mit.edu ;; Query time: 32 msec real 0m0.468s user 0m0.068s sys 0m0.028s
example second run
ibm.com ;; Query time: 0 msec yahoo.com ;; Query time: 0 msec google.com ;; Query time: 0 msec oracle.com ;; Query time: 0 msec bmw.com ;; Query time: 0 msec audi.com ;; Query time: 0 msec cnn.com ;; Query time: 0 msec bbc.com ;; Query time: 0 msec dw.com ;; Query time: 0 msec wikipedia.org ;; Query time: 0 msec mit.edu ;; Query time: 0 msec real 0m0.110s user 0m0.080s sys 0m0.012s
