User talk:Jch

Building_a_complete_infrastucture_with_AL

From first repo:

apk add AlpineLinux dhcpd tftp-hpa syslinux mkinitfs nfs-utils darkhttpd rsync openssh openvswitch screen qemu-system-X86_64 qemu-img parted mdadm lvm2 nbd consul dnsmasq vim collectd collectd-network git syslog-ng

Soon:

apk add envconsul consul-template xnbd ceph

To use it add:

apk add lxc lxc-templates xfsprogs gptfdisk e2fsprogs multipath wipe

To debug it add:

apk add tcpdump

and activate a collectd server and a syslog one.

To enable services join the internet and add official repo trough some squid proxy.

About NFS

NFS is now working with AL. Both as server and client with the nfs-utils package.
However, to use NFS as client in some LXC does not seems to work yet as shown below

nfstest:~# mount -t nfs -o ro 192.168.1.149:/srv/boot/alpine /mnt
mount.nfs: Operation not permitted
mount: permission denied (are you root?)
nfstest:~# tail /var/log/messages 
Apr  4 10:05:59 nfstest daemon.notice rpc.statd[431]: Version 1.3.1 starting
Apr  4 10:05:59 nfstest daemon.warn rpc.statd[431]: Flags: TI-RPC 
Apr  4 10:05:59 nfstest daemon.warn rpc.statd[431]: Failed to read /var/lib/nfs/state: Address in use
Apr  4 10:05:59 nfstest daemon.notice rpc.statd[431]: Initializing NSM state
Apr  4 10:05:59 nfstest daemon.warn rpc.statd[431]: Failed to write NSM state number: Operation not permitted
Apr  4 10:05:59 nfstest daemon.warn rpc.statd[431]: Running as root.  chown /var/lib/nfs to choose different user
nfstest:~# ls -l /var/lib/nfs
total 12
-rw-r--r--    1 root     root             0 Nov 10 15:43 etab
-rw-r--r--    1 root     root             0 Nov 10 15:43 rmtab
drwx------    2 nobody   root          4096 Apr  4 10:05 sm
drwx------    2 nobody   root          4096 Apr  4 10:05 sm.bak
-rw-r--r--    1 root     root             4 Apr  4 10:05 state
-rw-r--r--    1 root     root             0 Nov 10 15:43 xtab

msg from ncopa """ dmesg should tell you that grsecurity tries to prevent you to do this.

grsecurity does not permit the syscall mount from within a chroot since that is a way to break out of a chroot. This affects lxc containers too.

I would recommend that you do the mouting from the lxc host in the container config with lxc.mount.entry or similar.

https://linuxcontainers.org/lxc/manpages/man5/lxc.container.conf.5.html#lbAR

If you still want disable mount protection in grsecurity then you can do that with: echo 0 > /proc/sys/kernel/grsecurity/chroot_deny_mount """

this is not working with

lxc.mount.entry=nfsserver:/srv/boot/alpine mnt nfs nosuid,intr 0 0

on the host machine with all nfs modules and helper software installed and loaded.

backend:~# lxc-start -n nfstest
lxc-start: conf.c: mount_entry: 2049 Invalid argument - failed to mount
'nfsserver:/srv/boot/alpine' on '/usr/lib/lxc/rootfs/mnt'
lxc-start: conf.c: lxc_setup: 4163 failed to setup the mount entries for
'nfstest'
lxc-start: start.c: do_start: 688 failed to setup the container
lxc-start: sync.c: __sync_wait: 51 invalid sequence number 1. expected 2
lxc-start: start.c: __lxc_start: 1080 failed to spawn 'nfstest'

Nor with

echo 0 > /proc/sys/kernel/grsecurity/chroot_deny_mount

on the host machine with all nfs modules and helper software installed and loaded which does'nt work either.

To find a proper way to use NFS shares from AL LXC is an important topic in order to be able to, for instance, load balance web servers sharing contents uploaded by users.

Next step will be to have HA for the NFS server itself (with only AL machines).

About NBD

NBD is now in edge/testing thanks to clandmeter.

I cannot test it properly at the moment because all the machine are busy in prod. and this package allows newstyle only. I'm waiting my new lab machine...

We still miss xnbd fot it's proxy features allowing live migration. We are very exited by xnbd capacities!
Will be avid tester!

Also we are still looking after the right solution to backup NBD as a whole (versus by it's content) while in use. dd|nc is the used way nowadays.

About consul

nothing yet but big hopes ^^
I'm lurking IRC about it ;)

We plan to use it's dynamic DNS feature, it's hosts listing, services inventory, events, k/v store...
and even semi high-availability for our PXE infrastructure the consul leader being the active PXEserver and other consul server are dormant PXEservers.
All config scripts adapted to pull values out of consul k/v datastore based on profiles found out of consul various lists.
As the key for dhcpd and PXEboot is the hwaddr, it will become our uuid for LAN and consul too.
We are very exited by consul capacities!
Will be avid tester!

Open questions:

1. What memory footprint is needed?
2. What about dynamycally adapt quorum size?
3. Are checks possible triggers?

   • consul watch -prefix type -name name /path/to/executable

   • consul event [options] -name name [payload]

4. What best practice to store etc configurations?
   • http://code.hootsuite.com/distributed-configuration-management-and-dark-launching-using-consul/
   • http://agiletesting.blogspot.fr/2014/11/service-discovery-with-consul-and.html
   • envconsul
   • consul-template

log of experimentation at User_talk:Jch/consul

About CEPH

CEPH is supposed to sovle the problem of high availability for the data stores, be it block devices (disks) or character devices (files).

The actual situation is not satisfactory.

We are very exited by CEPH capacities!
Will be avid tester!

About Docker

not a lot of information on the Docker page yet ...