Marc
You are correct that my shell script is not most robust - it should be
re-written in java - and called upon on "graceful" shutdown - this
script should be treated as POC i guess.
What it guards against - is more than just snapshots though. Basically -
any async operation that would be harmful to end user experience if i
was to take down one of the MS servers.
I front my MS servers with a VIP, as i take down one of the MS servers
gracefully via script below, the agents all reconnect to next MS.
The current "Cold Cross Cluster" migration as it stands is done by
copying the data disk to secondary and then back to primary. If you have
a VMs with 4TB data disks - thats not feasible for several reasons (1
NFS export for SSVM may not be as large, its pretty slow to copy to NFS
and back to Primary - even if you have a robust network). Hence direct
migration bypassing the secondary store would be far more efficient.
In regards to secure KVM migration, each migrate call, establishes a
one-time SSH key pair between 2 KVM host that will be used only for the
duration of that migration. It is cleared once the operation completes
and avoids a possibility of someone exploiting the cloud user ssh keys.
This is not a big deal to Cloud Hosting companies - but is a big deal to
enterprise security folks who run cloudstack as private cloud. We don't
want cloud user keys littered everywhere - not very ideal in terms of
security.
Regards
ilya
On 7/3/16 10:41 PM, ma...@exoscale.ch wrote:
> Hi Ilya,
>
> Regarding the live migration, we are using it in production and did migrate a
> couple of VMs until we reach some corner cases, for which I wrote a few
> fixes. We'll verify them during the following weeks. The code is based on CS
> 4.4 but I started porting it to master. I have to finish that and merge the
> fixes too. For the cold migration, it's already in CS and we are usign it
> since a while.
> What do you mean by secure KVM migration? My code reads configuration values
> for which you can have TLS peer-2-peer connection between the agents to
> transfert over it all the data using the features in libvirt. That the setup
> we have in production.
>
> For the graceful shutdown, we have a HA proxy in front so we just edit the
> configuration to turn off one MS. We are also checking manually if there
> aren't any snapshot ongoing before launching the stop-start. But I don't find
> this very robust. Therefore I read a lot of the code managing the agent and
> how the agents are connected to the MS. There is already a command to
> rebalance agents between MS, so I'm developping a solution around that.
>
> Kind regards,
> Marc-Aurèle
>
>
>> On 02 Jul 2016, at 02:03, ilya <ilya.mailing.li...@gmail.com> wrote:
>>
>> Marco,
>>
>> I written a tiny shell script that does following:
>>
>> Make's sure there are async_jobs that arent running, also block 8080 via
>> iptables - to avoid user connecting to MS thats about to go down.
>>
>> It needs a bit of enhancement - and should lookup the MSID of that
>> specific server, it looks something like this - consider borrowing
>> concepts if applicable..
>>
>>> #!/bin/bash
>>> DATESTAMP=$(date +%m%d%y-%H%M%S)
>>> DBPASS=$(java -classpath /usr/share/cloudstack-common/lib/jasypt-1.9.0.jar
>>> org.jasypt.intf.cli.JasyptPBEStringDecryptionCLI input="$(cat
>>> /etc/cloudstack/management/db.properties | grep db.cloud.password | awk
>>> -F'(' '{print $2}' | sed 's/)//g')" password="$(cat
>>> /etc/cloudstack/management/key)" | grep -A2 OUTPUT | tail -1)
>>> DBHOST=$(cat /etc/cloudstack/management/db.properties | grep db.cloud.host
>>> | awk -F'=' '{print $2}' | tail -1 )
>>> DBUSER=$(cat /etc/cloudstack/management/db.properties | grep
>>> db.cloud.username | awk -F'=' '{print $2}')
>>> DB=$(cat /etc/cloudstack/management/db.properties | grep db.cloud.name |
>>> awk -F'=' '{print $2}')
>>> DBPORT=$(cat /etc/cloudstack/management/db.properties | grep db.cloud.port
>>> | awk -F'=' '{print $2}')
>>> MYSQLCMD="mysql -h $DBHOST -u $DBUSER -P $DBPORT -p$DBPASS $DB"
>>> #echo $DBPASS $DBHOST $DBUSER $DB $DBPORT
>>>
>>>
>>> JOBS=$(echo 'SELECT * FROM cloud.async_job where job_status=0 and
>>> job_dispatcher not like "pseudoJobDispatcher"' | $MYSQLCMD | wc -l)
>>>
>>> if [ $JOBS -gt 0 ]
>>> then
>>> echo "WARN: Looks like i have active jobs in flight, please
>>> try again later"
>>> echo 'SELECT * FROM cloud.async_job where job_status=0 and
>>> job_dispatcher not like "pseudoJobDispatcher"' | $MYSQLCMD
>>> exit
>>> else
>>> echo "NOTE: No jobs running, good to go!"
>>> echo "NOTE: Blocking incoming 8080"
>>> /sbin/iptables -A INPUT -p tcp --destination-port 8080 -j
>>> DROP
>>> service cloudstack-management stop
>>> service cloudstack-management stop:wq
>>> CSPID=$(cat /var/run/cloudstack-management.pid )
>>> ps -p $CSPID >/dev/null 2>&1 && (kill -9 $CSPID)
>>> ps -p $CSPID >/dev/null 2>&1 && (echo "ERROR: Count not
>>> terminame cloudstack service on `hostname` with pid $SCPID"; /sbin/iptables
>>> -D INPUT -p tcp --destination-port 8080 -j DROP; exit 1)
>>> service cloudstack-management start
>>> echo "NOTE: Unblocking incoming 8080"
>>> /sbin/iptables -D INPUT -p tcp --destination-port 8080 -j
>>> DROP
>>> fi
>>
>> Regards,
>> ilya
>>
>> On 7/1/16 3:30 AM, ma...@exoscale.ch wrote:
>>> Hi,
>>>
>>> I can't edit the page but I'll be glad to put some effort for the V5:
>>> - Live migration for KVM
>>> - Improve logging using UUIDs (as I already did part of that for us at
>>> exoscale)
>>>
>>> I'm in the process to add another feature we need: graceful shutdown of a
>>> management server when running a cluster of MS. The goal is to send a
>>> "prepareForShutdown" command to one or more MS and have them rebalance
>>> their agents to the ones still running so that no command will be lost.
>>> Then there shouldn't be any downtime with any agent during an update.
>>>
>>> Kind regards,
>>> Marc-Aurèle
>>>
>>> PS: Is there any architectural discussion going on on the Slack channel? I
>>> saw that the IRC is not so active...
>>>
>>>
>>>> On 01 Jul 2016, at 11:55, Paul Angus <paul.an...@shapeblue.com> wrote:
>>>>
>>>> There's not been much response to this, but I'll start clearing away the
>>>> unclaimed items, people can always add them back.
>>>>
>>>>
>>>> Kind regards,
>>>>
>>>> Paul Angus
>>>>
>>>>
>>>> paul.an...@shapeblue.com
>>>> www.shapeblue.com
>>>> 53 Chandos Place, Covent Garden, London WC2N 4HSUK
>>>> @shapeblue
>>>>
>>>>
>>>>
>>>
>
