Martin, thanks a lot for the information. This is very interesting, and i will contact again if we decided to go this way. best regards, samuel huxiaoyu@xxxxxxxxxxxx From: Martin Verges Date: 2020-03-22 20:50 To: huxiaoyu@xxxxxxxxxxxx CC: ceph-users Subject: Re: Questions on Ceph cluster without OS disks Hello Samuel, we from croit.io don't use NFS to boot up Servers. We copy the OS directly into the RAM (approximately 0.5-1GB). Think of it like a container, you start it and throw it away when you no longer need it. This way we can save the slots of OS harddisks to add more storage per node and reduce overall costs as 1GB ram is cheaper then an OS disk and consumes less power. If our management node is down, nothing will happen to the cluster. No impact, no downtime. However, you do need the mgmt node to boot up the cluster. So after a very rare total power outage, your first system would be the mgmt node and then the cluster itself. But again, if you configure your systems correct, no manual work is required to recover from that. For everything else, it is possible (but definitely not needed) to deploy our mgmt node in active/passive HA. We have multiple hundred installations worldwide in production environments. Our strong PXE knowledge comes from more than 20 years of datacenter hosting experience and it never ever failed us in the last >10 years. The main benefits out of that: - Immutable OS freshly booted: Every host has exactly the same version, same library, kernel, Ceph versions,... - OS is heavily tested by us: Every croit deployment has exactly the same image. We can find errors much faster and hit much fewer errors. - Easy Update: Updating OS, Ceph or anything else is just a node reboot. No cluster downtime, No service Impact, full automatic handling by our mgmt Software. - No need to install OS: No maintenance costs, no labor required, no other OS management required. - Centralized Logs/Stats: As it is booted in memory, all logs and statistics are collected on a central place for easy access. - Easy to scale: It doesn't matter if you boot 3 oder 300 nodes, all boot the exact same image in a few seconds. .. lots more Please do not hesitate to contact us directly. We always try to offer an excellent service and are strongly customer oriented. -- Martin Verges Managing director Mobile: +49 174 9335695 E-Mail: martin.verges@xxxxxxxx Chat: https://t.me/MartinVerges croit GmbH, Freseniusstr. 31h, 81247 Munich CEO: Martin Verges - VAT-ID: DE310638492 Com. register: Amtsgericht Munich HRB 231263 Web: https://croit.io YouTube: https://goo.gl/PGE1Bx Am Sa., 21. März 2020 um 13:53 Uhr schrieb huxiaoyu@xxxxxxxxxxxx <huxiaoyu@xxxxxxxxxxxx>: Hello， Martin， I notice that Croit advocate the use of ceph cluster without OS disks, but with PXE boot. Do you use a NFS server to serve the root file system for each node? such as hosting configuration files, user and password, log files, etc. My question is, will the NFS server be a single point of failure? If the NFS server goes down, the network experience any outage, ceph nodes may not be able to write to the local file systems, possibly leading to service outage. How do you deal with the above potential issues in production? I am a bit worried... best regards, samuel huxiaoyu@xxxxxxxxxxxx _______________________________________________ ceph-users mailing list -- ceph-users@xxxxxxx To unsubscribe send an email to ceph-users-leave@xxxxxxx
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