It seems as you don't have enought free space on your esxi server. have a look how much free space you have on /tmp
2015-05-15T16:42:59Z esxupdate: esxupdate: ERROR: An esxupdate error exception was caught:
2015-05-15T16:42:59Z esxupdate: esxupdate: ERROR: Traceback (most recent call last):
2015-05-15T16:42:59Z esxupdate: esxupdate: ERROR: File "/usr/sbin/esxupdate", line 216, in main
2015-05-15T16:42:59Z esxupdate: esxupdate: ERROR: cmd.Run()
2015-05-15T16:42:59Z esxupdate: esxupdate: ERROR: File "/build/mts/release/bora-2302651/bora/build/esx/release/vmvisor/sys-boot/lib/python2.6/site-packages/vmware/esx5update/Cmdline.py", line 106, in Run
2015-05-15T16:42:59Z esxupdate: esxupdate: ERROR: File "/build/mts/release/bora-2302651/bora/build/esx/release/vmvisor/sys-boot/lib/python2.6/site-packages/vmware/esximage/Transaction.py", line 69, in DownloadMetadatas
2015-05-15T16:42:59Z esxupdate: esxupdate: ERROR: File "/build/mts/release/bora-2302651/bora/build/esx/release/vmvisor/sys-boot/lib/python2.6/site-packages/vmware/esximage/Downloader.py", line 268, in Get
2015-05-15T16:42:59Z esxupdate: esxupdate: ERROR: File "/build/mts/release/bora-2302651/bora/build/esx/release/vmvisor/sys-boot/lib/python2.6/site-packages/vmware/esximage/Downloader.py", line 170, in _getfromurl
2015-05-15T16:42:59Z esxupdate: esxupdate: ERROR: File "/build/mts/release/bora-2302651/bora/build/esx/release/vmvisor/sys-boot/lib/python2.6/site-packages/urlgrabber/grabber.py", line 927, in urlgrab
2015-05-15T16:42:59Z esxupdate: esxupdate: ERROR: File "/build/mts/release/bora-2302651/bora/build/esx/release/vmvisor/sys-boot/lib/python2.6/site-packages/urlgrabber/grabber.py", line 845, in _retry
2015-05-15T16:42:59Z esxupdate: esxupdate: ERROR: File "/build/mts/release/bora-2302651/bora/build/esx/release/vmvisor/sys-boot/lib/python2.6/site-packages/urlgrabber/grabber.py", line 915, in retryfunc
2015-05-15T16:42:59Z esxupdate: esxupdate: ERROR: File "/build/mts/release/bora-2302651/bora/build/esx/release/vmvisor/sys-boot/lib/python2.6/site-packages/urlgrabber/grabber.py", line 1219, in _do_grab
2015-05-15T16:42:59Z esxupdate: esxupdate: ERROR: IOError: [Errno 28] No space left on device