"Temporary failure in name resolution" error while NSX host preparation & while performing VUM tasks on ESXi host

Products

• VMware vCenter Server
• VMware vSphere ESXi
• VMware NSX

Issue/Introduction

Symptoms:

• NSX host preparation fails
• Unable to perform VUM tasks on ESXi, error "Host cannot download files from VMWare vSphere Update Manager patch store.Check the network connectivity and firewall setup and check esxupdate logs for details"
• You will see the similar entries in esxupdate.log file

esxupdate.log

2020-02-21T01:06:36Z esxupdate: 761348: downloader: DEBUG: Downloading http://vcfqdn:9084/vum/repository/hostupdate/Unknown/metadata_1527045938.zip to /tmp/tmpqfUfjc...^@
2020-02-21T01:08:22Z esxupdate: 761348: esxupdate: ERROR: An esxupdate error exception was caught:^@
2020-02-21T01:08:22Z esxupdate: 761348: esxupdate: ERROR: Traceback (most recent call last):^@
2020-02-21T01:08:22Z esxupdate: 761348: esxupdate: ERROR:   File "/usr/sbin/esxupdate", line 238, in main^@
2020-02-21T01:08:22Z esxupdate: 761348: esxupdate: ERROR:     cmd.Run()^@
2020-02-21T01:08:22Z esxupdate: 761348: esxupdate: ERROR:   File "/build/mts/release/bora-13635687/bora/build/esx/release/vmvisor/sys-boot/lib/python2.7/site-packages/vmware/esx5update/Cmdline.py", line 105, in Run^@
2020-02-21T01:08:22Z esxupdate: 761348: esxupdate: ERROR:   File "/build/mts/release/bora-13635687/bora/build/esx/release/vmvisor/sys-boot/lib/python2.7/site-packages/vmware/esximage/Transaction.py", line 73, in DownloadMetadatas^@
2020-02-21T01:08:22Z esxupdate: 761348: esxupdate: ERROR: MetadataDownloadError: ('http://vcfqdn:9084/vum/repository/hostupdate/Unknown/metadata_1527045938.zip', None, "('http://vcfqdn:9084/vum/repository/hostupdate/Unknown/metadata_1527045938.zip', '/tmp/tmpqfUfjc', '[Errno 4] IOError: <urlopen error [Errno -3] Temporary failure in name resolution>')")^@
2020-02-21T01:08:22Z esxupdate: 761348: esxupdate: DEBUG: <<<^@

 

• Log file: /var/log/esxupdate.log

Options: {'nosigcheck': None, 'retry': 5, 'loglevel': None, 'cleancache': None, 'viburls': None, 'meta': ['https://vcenter.local:443/eam/vib?id=15b15745-6255-4f4c-b9eb-e55d9f6d1ed4'], 'proxyurl': None, 'timeout': 30.0, 'cachesize': None, 'hamode': True, 'maintenancemode': None}^@
2017-06-01T12:19:27Z esxupdate: 49174: vmware.runcommand: INFO: runcommand called with: args = '['/sbin/bootOption', '-rp']', outfile = 'None', returnoutput = 'True', timeout = '0.0'.^@
2017-06-01T12:19:27Z esxupdate: 49174: vmware.runcommand: INFO: runcommand called with: args = '['/sbin/bootOption', '-ro']', outfile = 'None', returnoutput = 'True', timeout = '0.0'.^@
2017-06-01T12:19:28Z esxupdate: 49174: downloader: DEBUG: Downloading https://vcenter.local:443/eam/vib?id=15b15745-6255-4f4c-b9eb-e55d9f6d1ed4 to /tmp/tmpCIjuiR...^@
2017-06-01T12:22:53Z esxupdate: 49174: esxupdate: ERROR: An esxupdate error exception was caught:^@
2017-06-01T12:22:53Z esxupdate: 49174: esxupdate: ERROR: Traceback (most recent call last):^@
2017-06-01T12:22:53Z esxupdate: 49174: esxupdate: ERROR: File "/usr/sbin/esxupdate", line 238, in main^@
2017-06-01T12:22:53Z esxupdate: 49174: esxupdate: ERROR: cmd.Run()^@
2017-06-01T12:22:53Z esxupdate: 49174: esxupdate: ERROR: File "/build/mts/release/bora-5224934/bora/build/esx/release/vmvisor/sys-boot/lib/python2.7/site-packages/vmware/esx5update/Cmdline.py", line 105, in Run^@
2017-06-01T12:22:53Z esxupdate: 49174: esxupdate: ERROR: File "/build/mts/release/bora-5224934/bora/build/esx/release/vmvisor/sys-boot/lib/python2.7/site-packages/vmware/esximage/Transaction.py", line 73, in DownloadMetadatas^@
2017-06-01T12:22:53Z esxupdate: 49174: esxupdate: ERROR: MetadataDownloadError: ('https://vcenter.local:443/eam/vib?id=15b15745-6255-4f4c-b9eb-e55d9f6d1ed4', None, "('https://vcenter.local:443/eam/vib?id=15b15745-6255-4f4c-b9eb-e55d9f6d1ed4', '/tmp/tmpCIjuiR', '[Errno 4] IOError: <urlopen error [Errno -3] Temporary failure in name resolution>')")^@
2017-06-01T12:22:53Z esxupdate: 49174: esxupdate: DEBUG: <<<^@

Note: The preceding log excerpts are only examples. Date, time, and environmental variables may vary depending on your environment.

Environment

VMware vSphere ESXi 6.0

Resolution

NSX:

• To assist on further troubleshooting this issue, check the DNS settings for the host(s) being prepared. For more information, see Configuring VMware ESXi Management Network from the direct console.

VUM:

• ESXi is not able to resolve vcenter FQDN and IP.
• Check using nslookup on esxi.
• Update correct DNS entries on ESXi.