validate overall report: some tests failed:
./test-all-tcp ./test-all-testReno ./test-all-newreno ./test-all-sack ./test-all-tcpOptions ./test-all-tcpReset ./test-all-testReno-full ./test-all-testReno-bayfull ./test-all-sack-full ./test-all-tcp-init-win ./test-all-tcpVariants ./test-all-LimTransmit ./test-all-aimd ./test-all-rfc793edu ./test-all-rfc2581 ./test-all-rbp ./test-all-tcpLinux ./test-all-frto ./test-all-ecn ./test-all-ecn-ack ./test-all-ecn-full ./test-all-quickstart ./test-all-manual-routing ./test-all-red ./test-all-adaptive-red ./test-all-red-pd ./test-all-rio ./test-all-vq ./test-all-rem ./test-all-gk ./test-all-pi ./test-all-cbq ./test-all-schedule ./test-all-links ./test-all-oddBehaviors
to re-run a specific test, cd tcl/test; ./test-all-TEST-NAME

I got this error while validating ns2 in ubuntu 14.04

Welcome to LQ.

Missing information in your question : The ns2 version.

./validate runs about 100 group tests. ( ./test-all-tcp ... etc. etc.)
The 100 group tests are running about 2000 individual tests.
Some (always) will fail with a modern 'Linux OS'.
... I.e. ns2 is old code, mostly meant for a ~10 year old OS.
(Your test : Some tests included in 35 group tests are failing.)

About 'validate' : No reason to run validate.
Nothing you can do when failing some tests.
And all simulations are usually working OK.

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