Uptime objectives » History » Version 4
Nico Schottelius, 07/01/2019 07:33 PM
1 | 1 | Nico Schottelius | h1. Uptime objectives |
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3 | 2 | Nico Schottelius | {{toc}} |
4 | 1 | Nico Schottelius | |
5 | 4 | Nico Schottelius | h2. Uptime definitons |
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8 | | % | Downtime / year | |
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9 | | 99 | 87h or 3.65 days | |
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10 | | 99.9 | 8.76h | |
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11 | | 99.99 | 0.876h or 52.55 minutes | |
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12 | | 99.999 | 5.25 minutes | |
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14 | 1 | Nico Schottelius | h2. Power Supply |
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16 | * What: Power supply to all systems |
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17 | * Setup: |
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18 | ** Core systems are connected to UPS that last between 7-30 minutes |
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19 | 4 | Nico Schottelius | ** Virtualisation systems are not (yet) fully connected to UPS (to be finished 2019-07) |
20 | * Uptime objective |
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21 | ** Prior to full UPS installation: <= 24h/year (99%) |
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22 | ** After UPS installation: 99.9% |
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23 | *** Probably less, as most power outages are <1m |
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24 | 1 | Nico Schottelius | |
25 | |||
26 | h2. Internal Network |
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27 | |||
28 | * What: The connection between servers, routers and switches. |
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29 | * Setup: All systems are connected twice internally, usually via fiber |
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30 | * Expected outages |
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31 | ** Single switch outage: no outage, maybe short packet loss (LACP link detection might take some seconds) |
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32 | ** Double switch outage: full outage, manual replacement |
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33 | * Uptime objectives |
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34 | 4 | Nico Schottelius | ** From 2019: >= 99.999% |
35 | 1 | Nico Schottelius | |
36 | |||
37 | h2. L2 external Network |
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38 | |||
39 | * What: the network between the different locations |
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40 | * Setup: |
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41 | ** Provided by local (electricity) companies. |
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42 | ** No additional active equipment / same as internal network |
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43 | * Expected outages |
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44 | ** 1 in 2018 that could be bridged by Wifi |
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45 | ** If an outage happens, it's long (digging through the cable) |
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46 | ** But it happens very rarely |
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47 | ** Mid term geo redundant lines planned |
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48 | 4 | Nico Schottelius | ** Geo redundancy might be achieved starting 2020 |
49 | 1 | Nico Schottelius | * Uptime objectives |
50 | ** 2019: >= 99.99% |
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51 | 4 | Nico Schottelius | ** 2020: >= 99.999% |
52 | ** 2021: >= 99.999% |
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53 | 1 | Nico Schottelius | |
54 | |||
55 | h2. L3 external Network |
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56 | |||
57 | * What: the external (uplink) networks |
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58 | * Setup |
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59 | 4 | Nico Schottelius | ** Currently 2 uplinks |
60 | ** Soon 2 individual plus a third central uplink |
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61 | 1 | Nico Schottelius | * Expected outages |
62 | 4 | Nico Schottelius | ** 2019 added bgp support |
63 | ** Outage simulations still due |
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64 | 1 | Nico Schottelius | * Uptime objectives |
65 | 4 | Nico Schottelius | ** 2019: >= 99.99% |
66 | ** 2020: >= 99.999% |
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67 | ** 2021: >= 99.999% |
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68 | 1 | Nico Schottelius | |
69 | |||
70 | h2. Routers |
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71 | |||
72 | 4 | Nico Schottelius | * What: the central routers |
73 | * Setup |
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74 | ** Two routers running Linux with keepalived |
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75 | ** Both routers are rebooted periodically -> downtime during that time is critical, but unlikely |
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76 | ** Routers are connected to UPS |
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77 | ** Routers are running raid1 |
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78 | * Expected outages |
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79 | ** Machines are rather reliable |
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80 | ** If one machines has to be replaced, replacement can be prepared while other routers are active |
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81 | ** Rare events, nice 2017 no router related downtime |
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82 | * Uptime objectives |
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83 | ** 2019: >= 99.99% |
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84 | ** 2020: >= 99.999% |
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85 | ** 2021: >= 99.999% |
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86 | 1 | Nico Schottelius | |
87 | |||
88 | h2. Servers |
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89 | |||
90 | * What: Servers host VMs and in case of a defect VMs need to be restarted on a different server |
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91 | * Setup: |
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92 | ** Servers are dual power connected |
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93 | ** Servers are used hardware |
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94 | ** Servers are being monitored (prometheus+consul) |
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95 | 3 | Nico Schottelius | ** Not yet sure how to detect soon failng servers |
96 | 4 | Nico Schottelius | ** So far 3 servers affected (out of about 30) |
97 | * Expected outages |
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98 | ** At the moment servers "run until they die" |
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99 | ** In the future servers should be periodically rebooted to detect broken hardware (live migrations enable this) |
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100 | ** While a server downtime effects all VMs (up to 100 per server), it's a rare event |
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101 | * Uptime objectives (per VM) |
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102 | ** 2019: >= 99.99% |
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103 | ** 2020: >= 99.999% |
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104 | ** 2021: >= 99.999% |