f.haeder.net

S9 Antminer's root password "admin" - change immediately!!!

I now own a #S9 #Antminer from #Bitmain for some weeks (already). It runs really loud and I turn it only on when I'm out of house or want to have it running. It has a nice web interface and even #SSH with root (some #Linux embeded system). I setup quickly everthing and mining #Peercoins is working as expected (I run it in eco-mode). But what I later found out is that the SSH root password is simply "admin" which is a well-known password.

So here is my advice: If you intend to buy and run it (locally or on public Internet) please *do change* your SSH password! If you fail to do so, somebody might be able to change your pool login data and then he is receiving the coins you want to mine on your electricity bill! And I'm sure that he will then change root password to his own so you have to (somehow?) flush the memory to have factory-default settings (including password, I hope) back.

Here are some pictures of my miner, including screenshots which is just below my computer table (and it can be very noisy): #Nextcloud
#S9 #Antminer #Bitmain #SSH #Linux #Peercoins #Nextcloud antminer bitmain hijacking password root s9

Why is Linux not using more RAM for caching?

I have this on my server:
___________total       used       free     shared    buffers     cached
Mem:       7939312    6490588    1448724          0      66760     192064
-/+ buffers/cache:    6231764    1707548
Swap:     12485748     189256   12296492

So there is a 1 GB RAM (not much, I know) left but #Linux is not using it for caching which would greatly improve performance (it really does). vm.swappiness is 20 here.

Here are all cache settings:
# sysctl -a|grep cache
kernel.sched_domain.cpu0.domain0.cache_nice_tries = 1
kernel.sched_domain.cpu1.domain0.cache_nice_tries = 1
kernel.sched_domain.cpu2.domain0.cache_nice_tries = 1
kernel.sched_domain.cpu3.domain0.cache_nice_tries = 1
vm.drop_caches = 0
vm.vfs_cache_pressure = 100
fs.quota.cache_hits = 0
net.ipv4.rt_cache_rebuild_count = 4
fscache.object_max_active = 4
fscache.operation_max_active = 2

Which do I need to change (except adding more RAM but that costs me monthly more).
#Linux linux optimizing sysadmin
I have a Quad-Core server running this instance and some pages more. What would you recommend when it comes to process priorities? More prio on database or on webserver?
newer older