I have a DHCPv6 daemon that is answering for requests of some machines and everything is working fine. So I decided to remove this DHCPv6 daemon e start another daemon on another server, but the problem now is that since all machines already have a long lease, they don't ask to renew the lease or to get a new lease. I know the solution would be restarting machines, restarting clients, using dhclient -r to release the lease, etc. But I can't do that, I only have the control of the new installed DHCPv6 server, is there any way to make DHCPv6 daemon to actively advertise to the clients something like that ? I'm using the ISC DHCP server.
I'm trying to design an architecture to handle massive TCP socket connections and I'm in doubt on the limits of this architecture.
I'll have to handle ~20k concurrent TCP connections and these are long-polling connections, they'll remain connected for long periods of time and will be sending data every minute.
Using threads is out of question, since 20k threads will starve the system resources. I'm planning to use gevent to handle such amount of concurrent connections or even use haproxy and 2 servers (w/ gevent) to handle 10k connections each for instance. Does that makes sense ? Does anyone have some advice or had some experience using gevent with 10K+ connections ? Does anyone have idea of the hardware requirements to handle these connections ? I saw some benchmarks that shows lots of connection timeouts for gevent on 5k concurrent connections, what is not very promising for my problem.
Note: I've already read about the C10k problem and the advices on the "Million-user Comet Application".
In ssh_config I have the HostKeyAlgorithms parameter where I can enforce the use of DSS algorithm for the key, like:
HostKeyAlgorithms "ssh-dss"
How can I do this in sshd_config (daemon config) in order to enforce that all connections incoming should use the ssh-dss instead of ssh-rsa ?
I have a bridge called "br01" in which the interfaces "eth1" and "eth0" are participating. There is a rule in the broute table of ebtables that drops RAs when they arrive in the interface eth1, so the eth1 auto-configure itself with this RA, but I want that this same RA go through the eth0 too, in order to distribute this RA to the other network which is on the eth0. Is there any way to do that ?
How can I disable IPv4 stack from Linux ? I want to do that dynamically, i.e. sometimes I want it enabled and sometimes I want only IPv6 stack. Is there any portable way to do that ? If you know how to do that in any distribution, it will also help me a lot.