Question
When attempting to upgrade, why do I get the following error:
Failure downloading upgrade list. (Error performing upgrade: I/O error).
Errors when trying to upgrade. Failure downloading upgrade list.
(Error performing upgrade: I/O error opening URL '<download URL>')?
There are a few reasons why this error may occur:
- Unable to resolve the upgrade server hostname via DNS (possibly negative cache entries)
- The interface being used for upgrades cannot communicate to the upgrades server.
See the solutions for each scenario below.
Unable to Resolve the Upgrade Server DNS (Possibly Negative Cache Entries)
To verify if a bad DNS is causing the issue, run the following CLI commands:
WSA.CLI > nslookup downloads.ironport.com
If there are no associated IP addresses returned, run the dnsflush command. This will force the WSA to re-request DNS for the upgrade server.
Is 'nslookup' of the domain "downloads.ironport.com" successful on the WSA?
-------------------------------------------------------------------------------------
- If No, then WSA is unable to resolve the hostname.
- In this case, it would be recommended to try another DNS server or check why
the configured DNS serveris not resolving the hostname for Cisco's update server
- If Yes, then use the CLI command "dnsflush" to flush the DNS cache & force the DNS lookup
WSA.CLI> dnsflush
Are you sure you want to clear out the DNS cache? [N]> y
The upgrade command can now be run successfully.
Check if the CLI command "upgrade" returns the error.
wsa.example.com (SERVICE)> upgrade
Failure downloading upgrade list. (Error performing upgrade: I/O error
opening URL
'http://downloads.ironport.com/asyncos/upgrade/?serial=<Serial_Number>
&version=<AsyncOS-version>&product=<WSA-Model>')
Example
wsa.example.com (SERVICE)> nslookup downloads.ironport.com
A=64.62.193.129 TTL=30m
A=64.62.193.134 TTL=30m
wsa.example.com (SERVICE)> dnsflush
Are you sure you want to clear out the DNS cache? [N]> y
wsa.example.com (SERVICE)>
wsa.example.com (SERVICE)> upgrade
Upgrades available:
1. AsyncOS 7.5.2 build 303 upgrade For Web .....
[1]>
The interface being used for upgrades cannot communicate to the
upgrades server
This error may also be returned if the incorrect interface is being used for upgrades.
When M1 and P1 interfaces are used, depending on the network deployment, it is possible that only the P1 interface has Internet access and should be the correct interface to use for upgrades. If the WSA is configured to use M1 in such cases, then it could cause the upgrade fetch to fail, resulting in the "Failure downloading ..." error.
Here are instructions for changing the upgrade interface via the CLI:
WSA.CLI> updateconfig
Upgrade source: http://downloads.qa/asyncos/upgrade/
Upgrade interface: AUTO
Proxy server: not in use
Choose the operation you want to perform:
- SETUP - Edit upgrade configuration.
[]> setup
Please select the upgrade source you want to use for AsyncOS updates:
1. Use Cisco update servers
2. Use own server
[1]> <Enter>
.......
Choose the routing table to use
1. Data
2. Management
[1]> 1
..... Press <Enter> till you reach the CLI prompt ......
WSA.CLI> commit
Note: Please note that the above changes will not take effect unless a 'commit' is issued.