61813e69f7
It's possible that a log file is created while this script is running, and if being created after we get the valid last_dom_ids then the log file may be deleted incorrectly. Also add some logging which can be used to trace any future race conditions Change-Id: I1df1a0775a7dae41105d6c41b046c86002eb5eec Closes-Bug: 1516721
64 lines
2.2 KiB
Bash
Executable File
64 lines
2.2 KiB
Bash
Executable File
#!/bin/bash
|
|
set -eux
|
|
|
|
# Script to rotate console logs
|
|
#
|
|
# Should be run on Dom0, with cron, every minute:
|
|
# * * * * * /root/rotate_xen_guest_logs.sh
|
|
#
|
|
# Should clear out the guest logs on every boot
|
|
# because the domain ids may get re-used for a
|
|
# different tenant after the reboot
|
|
#
|
|
# /var/log/xen/guest should be mounted into a
|
|
# small loopback device to stop any guest being
|
|
# able to fill dom0 file system
|
|
|
|
log_dir="/var/log/xen/guest"
|
|
kb=1024
|
|
max_size_bytes=$(($kb*$kb))
|
|
truncated_size_bytes=$((5*$kb))
|
|
syslog_tag='rotate_xen_guest_logs'
|
|
|
|
log_file_base="${log_dir}/console."
|
|
|
|
# Ensure logging is setup correctly for all domains
|
|
xenstore-write /local/logconsole/@ "${log_file_base}%d"
|
|
|
|
# Grab the list of logs now to prevent a race where the domain is
|
|
# started after we get the valid last_dom_ids, but before the logs are
|
|
# deleted. Add spaces to ensure we can do containment tests below
|
|
current_logs=$(find "$log_dir" -type f)
|
|
|
|
# Ensure the last_dom_id is set + updated for all running VMs
|
|
for vm in $(xe vm-list power-state=running --minimal | tr ',' ' '); do
|
|
xe vm-param-set uuid=$vm other-config:last_dom_id=$(xe vm-param-get uuid=$vm param-name=dom-id)
|
|
done
|
|
|
|
# Get the last_dom_id for all VMs
|
|
valid_last_dom_ids=$(xe vm-list params=other-config --minimal | tr ';,' '\n\n' | grep last_dom_id | sed -e 's/last_dom_id: //g' | xargs)
|
|
echo "Valid dom IDs: $valid_last_dom_ids" | /usr/bin/logger -t $syslog_tag
|
|
|
|
# Remove console files that do not correspond to valid last_dom_id's
|
|
allowed_consoles=".*console.\(${valid_last_dom_ids// /\\|}\)$"
|
|
delete_logs=`find "$log_dir" -type f -not -regex "$allowed_consoles"`
|
|
for log in $delete_logs; do
|
|
if echo "$current_logs" | grep -q -w "$log"; then
|
|
echo "Deleting: $log" | /usr/bin/logger -t $syslog_tag
|
|
rm $log
|
|
fi
|
|
done
|
|
|
|
# Truncate all remaining logs
|
|
for log in `find "$log_dir" -type f -regex '.*console.*' -size +${max_size_bytes}c`; do
|
|
echo "Truncating log: $log" | /usr/bin/logger -t $syslog_tag
|
|
tmp="$log.tmp"
|
|
tail -c $truncated_size_bytes "$log" > "$tmp"
|
|
mv -f "$tmp" "$log"
|
|
|
|
# Notify xen that it needs to reload the file
|
|
domid="${log##*.}"
|
|
xenstore-write /local/logconsole/$domid "$log"
|
|
xenstore-rm /local/logconsole/$domid
|
|
done
|