Differences

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--- unix:scripts:libvirt [2024/09/20 20:32] – created rodolico
+++ unix:scripts:libvirt [2024/09/20 21:23] (current) – rodolico
@@ Line 4: / Line 4: @@
 This little one liner grabs the lines that define the vnc ports used by all defined on a node (hypervisor) and returns them as a tab delimited string.
+==== Code ====
 <code bash>
@@ Line 22: / Line 24: @@
 libvirt (virsh) stores it's domain (virtual) definitions in /etc/libvirt/qemu/*.xml. The //grep// command only returns those lines (along with the file name) in the form
 <code>
-/media/shared/havirt/conf/andrei.dailydata.noc.xml:    <graphics type='vnc' port='5917' autoport='no' listen='127.0.0.1'>
+/etc/libvirt/qemu/andrei.dailydata.noc.xml:    <graphics type='vnc' port='5917' autoport='no' listen='127.0.0.1'>
 </code>
 We then pass those lines to a Perl one liner which grabs the filename (without the .xml) and the port, then prints them to STDOUT, tab separated. Using the -n flag to perl turns the one liner into a filter, which will run the code on all lines received via STDIN. For the above line, the following is sent to STDOUT
 <code>andrei.dailydata.noc	5917</code>
+==== Caveats ====
+  * If there is only one domain defined, grep does not return the filename, so the system breaks.
+  * This is totally dependent on how libvirt stores the data; path, key and whether the key is on the same line. Any changes to the libvirt storage will break the script.
+  * We use [[https://unixservertech.com/havirt/|havirt]] for our clusters. havirt stores the domain definitions in <installdir>/conf, so the grep command will need to be changed.