If you need a quick solution to "attach" a remote directory to your local server, SSHFS (Secure SHell FileSystem) is the answer. On the local computer, the remote share is mounted using FUSE (Filesystem in Userspace) kernel module.
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# install
\$ apt-get install sshfs -y
# check
\$ lsmod | grep fuse …
This is not a post about what is HeartBleed and how "evil" it is, I'm assuming you already heard about it ...
Anyway, you should find all the details at http://heartbleed.com/
Here is a collection of nice tools to play with:
You're running a service and you need to keep all the logs for a certain period of time (legal constraints or just internal retention policy). The logs are pretty big to be stored locally, so you need a big disk somewhere in the cloud - Google Cloud Storage comes to the …
This is not really an error, it's just an info message saying that the system cannot put the socket connection into time-wait state (buffer is full) and the socket will be closed. The reason for setting this limit is to resist simple DoS attacks.
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\$ dmesg | tail
[660665 …
A null client is a machine that can only send mail. It receives no mail from the network, and it does not deliver any mail locally.
This setup is useful when you need to receive the output of your cron scripts.
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\$ apt-get install postfix heirloom-mailx
\$ cat \<
Setup
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Client: ping from 50.50.50.50 to 30.30.30.30, gateway is 10.10.10.10
Server1: eth0 - 10.10.10.10 - public
ipip1 - 192.168.1.1 - ipip tunnel to Server2
Server2: eth0 - 20.20.20.20 - public
ipip1 - 192.168.1.2 …
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# execute a process via "strace"
\$ strace sleep 1
execve("/bin/sleep", ["sleep", "1"], [/* 17 vars */]) = 0
brk(0) = 0x753000
access("/etc/ld.so.nohwcap", F_OK) = -1 ENOENT (No such file or
directory)
mmap(NULL, 8192, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS,
-1, 0) = 0x7f74b3eea000
access("/etc/ld.so.preload …
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\$ iotop --only --accumulated
Total DISK READ: 0.00 B/s | Total DISK WRITE: 0.00 B/s
TID PRIO USER DISK READ DISK WRITE SWAPIN IO> COMMAND
2264 be/4 root 0.00 B 0.00 B 0.00 % 0.34 % [flush-254:0]
162 be/3 root …
The beginning:
You have a WhiteBox ESXi host (6 Cores @ 3.2 GHz, 16G RAM, 2x500GB +
2x1TB DAS, free
ESXi
version - of course) and some VMs running on it.
One of the VMs is a Centreon Server (monitoring).
Everything is going well and you also decide to do some off-site …
The network adapter will not send frames larger than the configured MTU !
TCPdump hooks above the driver, and does not see what is sent on the wire. Rather it sees what is sent from the stack to the driver. The stack will send TCP LSO frames up to about 64K …