secondary role. It is possible that the remote node is primary, but only
because there was a role change and it didn't finish cleaning up (unmounting
file systems, etc.). If we detect such situation, wait for the remote node
to switch the role to secondary before accepting I/Os. If we don't wait for
it in that case, we will most likely cause split-brain.
MFC after: 1 week
our info about worker processes if any of them was terminated in the meantime.
This fixes the problem with 'hastctl status' running from a hook called on
split-brain:
1. Secondary calls a hooks and terminates.
2. Hook asks for resource status via 'hastctl status'.
3. The main hastd handles the status request by sending it to the secondary
worker who is already dead, but because signals weren't checked yet he
doesn't know that and we get EPIPE.
MFC after: 1 week
This way we know how to connect to secondary node when we are primary.
The same variable is used by the secondary node - it only accepts
connections from the address stored in 'remote' variable.
In cluster configurations it is common that each node has its individual
IP address and there is one addtional shared IP address which is assigned
to primary node. It seems it is possible that if the shared IP address is
from the same network as the individual IP address it might be choosen by
the kernel as a source address for connection with the secondary node.
Such connection will be rejected by secondary, as it doesn't come from
primary node individual IP.
Add 'source' variable that allows to specify source IP address we want to
bind to before connecting to the secondary node.
MFC after: 1 week
- HOLE - it simply turns all-zero blocks into few bytes header;
it is extremely fast, so it is turned on by default;
it is mostly intended to speed up initial synchronization
where we expect many zeros;
- LZF - very fast algorithm by Marc Alexander Lehmann, which shows
very decent compression ratio and has BSD license.
MFC after: 2 weeks
worker can ask the main privileged process to connect in worker's behalf
and then we can migrate descriptor using this socketpair to worker.
This is not really needed now, but will be needed once we start to use
capsicum for sandboxing.
MFC after: 1 week
to syslog if we run in background.
- Asserts in proto.c that method we want to call is implemented and remove
dummy methods from protocols implementation that are only there to abort
the program with nice message.
MFC after: 1 week
we expect to be open. Also assert that they point at expected type.
Because openlog(3) API is unable to tell us descriptor number it is using, we
have to close syslog socket, remember assert message in local buffer and if we
fail on assertion, reopen syslog socket and log the message.
MFC after: 1 week
master process only and pass changes to the worker processes over control
socket. This removes access to global namespace in preparation for capsicum
sandboxing.
MFC after: 2 weeks
It is possible that the parent process ignores some of them and sigtimedwait()
will never see them, eventhough they are masked.
The most common situation for this to happen is boot process where init(8)
ignores SIGHUP before starting to execute /etc/rc. This in turn caused
hastd(8) to ignore SIGHUP.
Reported by: trasz
Obtained from: Wheel Systems Sp. z o.o. http://www.wheelsystems.com
MFC after: 3 days
masking it.
This fixes bogus reports about hooks running for too long and other problems
related to garbage-collecting child processes.
Reported by: Mikolaj Golub <to.my.trociny@gmail.com>
MFC after: 3 days
This way the primary process inherits signal mask from the main process,
which fixes a race where signal is delivered to the primary process before
configuring signal mask.
Reported by: Mikolaj Golub <to.my.trociny@gmail.com>
MFC after: 3 days
limited to async-signal safe functions in the child process), move all hooks
execution to the main (non-threaded) process.
Do it by maintaining connection (socketpair) between child and parent
and sending events from the child to parent, so it can execute the hook.
This is step in right direction for others reasons too. For example there is
one less problem to drop privs in worker processes.
MFC after: 2 weeks
Obtained from: Wheel Systems Sp. z o.o. http://www.wheelsystems.com
- Load added resources.
- Stop and forget removed resources.
- Update modified resources in least intrusive way, ie. don't touch
/dev/hast/<name> unless path to local component or provider name were
modified.
Obtained from: Wheel Systems Sp. z o.o. http://www.wheelsystems.com
MFC after: 1 month
- Don't exit on errors if not requested.
- Don't keep configuration in global variable, but allocate memory for
configuration.
- Call yyrestart() before yyparse() so that on error in configuration file
we will start from the begining next time and not from the place we left of.
MFC after: 1 month
we grow more descriptors, but I'll reconsider readding them once we get there.
Passing (a = b) expression to FD_ISSET() is bad idea, as FD_ISSET() evaluates
its argument twice.
Found by: Coverity Prevent
CID: 5243
MFC after: 3 days
secondary, which died between send(2) and recv(2). Do it by adding timeout
to recv(2) for primary incoming and outgoing sockets and secondary outgoing
socket.
Reported by: Mikolaj Golub <to.my.trociny@gmail.com>
Tested by: Mikolaj Golub <to.my.trociny@gmail.com>
MFC after: 3 days
HAST allows to transparently store data on two physically separated machines
connected over the TCP/IP network. HAST works in Primary-Secondary
(Master-Backup, Master-Slave) configuration, which means that only one of the
cluster nodes can be active at any given time. Only Primary node is able to
handle I/O requests to HAST-managed devices. Currently HAST is limited to two
cluster nodes in total.
HAST operates on block level - it provides disk-like devices in /dev/hast/
directory for use by file systems and/or applications. Working on block level
makes it transparent for file systems and applications. There in no difference
between using HAST-provided device and raw disk, partition, etc. All of them
are just regular GEOM providers in FreeBSD.
For more information please consult hastd(8), hastctl(8) and hast.conf(5)
manual pages, as well as http://wiki.FreeBSD.org/HAST.
Sponsored by: FreeBSD Foundation
Sponsored by: OMCnet Internet Service GmbH
Sponsored by: TransIP BV
