Scale down of ambari cluster is not working in Openstack Train Sahara

When scaling down Ambari Cluster in Openstack Train Sahara, it is failed with error – object of type ‘filter’ has no len() in Cluster Event tab in Horizon. When doing the same using openstack client, it shows that cluster scaling down started, but it is not scaling down the cluster. in sahara-engine.log, cluster status changed to decommissioning and immediately it changes to active without showing any error.
Sahara engine log is :
2020-09-19 18:24:46.485 13644 WARNING sahara.context (-) Arguments dropped when creating context: {‘user’: ‘a89f302f93f144e29f6e1a8204e766eb’, ‘tenant’: ’66b30bbab9814815a678bd2be77ce435′, ‘system_scope’: None, ‘project’: ’66b30bbab9814815a678bd2be77ce435′, ‘domain’: None, ‘user_domain’: None, ‘project_domain’: None, ‘read_only’: False, ‘show_deleted’: False, ‘global_request_id’: None, ‘user_identity’: ‘a89f302f93f144e29f6e1a8204e766eb 66b30bbab9814815a678bd2be77ce435 – – -‘, ‘is_admin_project’: True, ‘user_name’: ‘admin’, ‘project_name’: ‘admin’, ‘client_timeout’: None}
2020-09-19 18:24:50.367 13644 INFO sahara.utils.cluster (req-b3317ce2-b72e-44e6-911f-94fb77cc4067 a89f302f93f144e29f6e1a8204e766eb 66b30bbab9814815a678bd2be77ce435 – – -) (instance: none, cluster: f3194133-331d-449d-90b7-5cbf335392a3) Cluster status has been changed. New status=Decommissioning
2020-09-19 18:24:50.368 13644 DEBUG sahara.utils.notification.sender (req-b3317ce2-b72e-44e6-911f-94fb77cc4067 a89f302f93f144e29f6e1a8204e766eb 66b30bbab9814815a678bd2be77ce435 – – -) (instance: none, cluster: f3194133-331d-449d-90b7-5cbf335392a3) Notification about cluster is going to be sent. Notification type=sahara.cluster.update _notify /usr/lib/python3/dist-packages/sahara/utils/notification/
2020-09-19 18:24:50.889 13644 DEBUG oslo_service.periodic_task (-) Running periodic task SaharaPeriodicTasks.update_job_statuses run_periodic_tasks /usr/lib/python3/dist-packages/oslo_service/
2020-09-19 18:24:50.890 13644 DEBUG sahara.service.periodic (req-6c34c65b-c29d-463d-8ffd-5e35af99217b – – – – -) Updating job statuses update_job_statuses /usr/lib/python3/dist-packages/sahara/service/
2020-09-19 18:24:51.344 13644 INFO sahara.utils.cluster (req-b3317ce2-b72e-44e6-911f-94fb77cc4067 a89f302f93f144e29f6e1a8204e766eb 66b30bbab9814815a678bd2be77ce435 – – -) (instance: none, cluster: f3194133-331d-449d-90b7-5cbf335392a3) Cluster status has been changed. New status=Active

national rail – How to find the best-priced UK train ticket combos for not-quite-round trip journeys?

I do a lot of walking and hiking in the UK. Frequently, I need to find the best combination of tickets that will get me to the start of the walk and then bring me home. This is simple if the walk starts and ends on the same train line, but gets tricky otherwise.

For example, if I start at Vauxhall, and I wanted to walk from Salfords to Chilworth, I think it’s Contactless from Vauxhall to Salfords, and a single Chilworth to Vauxhall.

If I wanted to walk from Chilworth to Brookwood, it seems like the cheapest combination would be a return ticket from Vauxhall to Chilworth and a single from Brookwood to Woking.

I found these by painstaking trial and error, and there must be a better way to search for these in general. Do any of the “split ticket” search engines have this as an option? If I instead of Chilworth to Brookwood, I wanted to walk all the way to Sunningdale, I don’t think that Sunningdale to Weybridge would cover me for the return trip, but what would the best combination be, and how to find these in general?

tickets – Which train stations near the oyster boundary have contactless validators on (train) platforms?

On lines that have a London terminus, which stations have contactless validators easily accessible?

Because of how comparatively cheap contactless fares are, it can be advantageous when travelling into or out of London to use a combination of contactless and paper tickets… however that means needing to touch in and touch out.

For example, Riddlesdown has an on-platform validator easily accessible, meaning if you are close to the correct carriage it would be feasible to jump out, validate and jump back in… At Amersham, there are no validators on the platforms, but the ticket gates are very close to the middle of the London-bound platform, which would make it feasible to validate as well.

Is there a list of stations close to the contactless boundary that have validators easily accessible from the train platforms?

public transport – How much transfer time do I need between ferry and train in Travemünde?

Finnlines has instructions for foot passengers on its website:

It contains the following mention:

Please be aware that there is no walkway from the Lübeck-Travemünde
Skandinavienkai train station to the Skandinavienkai Terminal.

As a foot passenger you will be taken off the ferry in a mini bus and driven to the terminal building. From there regular busses run to Lübeck and Travemünde.

So you can go to and plan a trip…

From: “Skandinavienkai Terminal, Lübeck””

To: Pretty much anywhere in Europe….

So there is no need to get to the train Skandinavienkai train station.

Note that for regional travel there is no need to buy tickets in advance, and since (as is common in Germany) the tariff system is mode-neutral you cannot even buy a ticket for the 7:39 train, even if you wanted to…

Do I have to validate train tickets in the UK?

I bought train tickets in the UK like this one:

UK rail ticket

I always swipe them on the barriers1 before boarding the train, but I never see anyone else doing it. I wonder if it is necessary, but people simply don’t care (or they have other kinds of passes), or if simply having the ticket is enough.

1 Barriers like those depicted below are already open when I board the train, which reinforces the idea that there could be another means to check the validity of tickets:

Barriers at the train station

Context: I got used to validating public transport tickets in France, where simply having a ticket on board is not sufficient, e.g. some tickets can be used for different trains, so you need to validate (“composter”) them before boarding. Since my UK ticket can also be used at different times, I wonder if they follow the same principle.

postgresql – DB design – routes to many train companies

I am looking for advice on good DB practice in the following scenario:

  • Table A (route):

    • ID
    • Origin
    • Destination
    • Time
    • Train Companies IDs
  • Table B (Train Company):

The problem with this is 1 route can use many train company IDs with connections, if I create 3rd table to connect route with each train company it uses, it will be basically many dup routes with just different train companies. I thoughts one option is to have Train Companies IDs as ARRAY with many IDs. Any other ideas welcome.

Tips to go transfer from train station Paris Nord to Paris Austerlitz

According to google maps, the fastest way to transfer from Paris Nord to Paris Austerlitz is by catching metro 5 and ride for fourteen stops. It’s a direct line that leaves every 4 minutes and only takes 15 minutes. As I’ve seen other pages recommending two metros and reserving at least an hour to travel this distance I would live to verify that this is correct.

Also If any Parisians could confirm recommend maybe any common mistakes not to make or any stations to stop off (I’ve got two hours to kill) then I would love to you hear from you.

(used the site search engine, no results).

Kind regards,


transferring from train arriving in Vienna to Vienna airport with more luggage then I can carry without a trolley

Last time I arrived by train in Wien Hauptbahnhof with 3 airplane checked baggage sized bags (23 kg each), transferred to a local train to Vienna Airport (Flughafen Wien) train station, and there was a big problem: there where no trolleys at the train platform for luggage, and there was quite a large distance to walk from the train station to the terminal.

I thought an airport train station of a major European airport in a very developed country would have luggage trolleys at the platforms, but no, at least I didn’t find them. And the train station wasn’t even connected with the airport, had to walk outside quite a distance, at least 100 meters.

If I had 4 bags to check-in this would have been impossible. I can hardly believe I am the only person wanting to transfer from Vienna Airport train station to the airport with more luggage then I can carry. Even if they had wheels (not all of the bags have wheels), I have only 2 hands to pull bags, putting 2 of them on top of the other two and trying to roll on the wheels of the lower 2 bags has only a small chance of working without breaking the bag’s wheels and the whole thing becoming un-steerable, because of the weight.

What are my options if I were to make this transfer next time with four bags?

uk – Park & Ride train station from East of London to Reading

From the London/Essex border, where is the nearest free or inexpensive Park & Ride station with a regular direct connection to Reading?

I imagine that it would be on the far side of the Dartford Crossing, but which? This is a one off, but might become a regular commute, so, depending on the train fair, it might even be better to go nearer to Reading that London? It’s a time/cost trade-off, but I don’t have any data on which to base the decision.