[SOLVED] how to install iscsi client properly (mga6)?

[magfan]

I have installed open-iscsi in mga6 but already the first attempt to discover iscsi targets fails:

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iscsiadm -m discovery -t st -p 192.168.10.10
sh: /etc/rc.d/init.d/iscsid: Datei oder Verzeichnis nicht gefunden
iscsiadm: can not connect to iSCSI daemon (111)!
sh: /etc/rc.d/init.d/iscsid: Datei oder Verzeichnis nicht gefunden
iscsiadm: can not connect to iSCSI daemon (111)!
iscsiadm: Cannot perform discovery. Initiatorname required.
iscsiadm: Could not perform SendTargets discovery: could not connect to iscsid

The program "iscsid" cannot be found. What do I have to change to make this running?

[wintpe]

I always use the following and it appears to work ok

iscsiadm --mode discoverydb --type sendtargets --portal 192.168.1.60 --discover

regards peter

[magfan]

Thank you, it works. I can even login a target. But I have to do this manually after every reboot. How can I change this?

[wintpe]

http://www.linuxpc.co.uk/index.php?opti ... &Itemid=54

thats for systems pre systemd, but it should not be too hard to make the conversion

hope that helps

regards peter

[jiml8]

I would think that

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systemctl enable open-iscsi.service


would do it.

I have iscsi running here, with a part of my NAS being the target, and it works fine with systemctl.

[magfan]

The open-iscsi.service is running, but I have to discover the targets every time after reboot. Once iscsiadm discovered them I can manually login. Should there be some configuration files in "/etc/iscsi/nodes" ? And if so, how could I create them?

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# tree /etc/iscsi/
/etc/iscsi/
├── ifaces
│   └── iface.example
├── initiatorname.iscsi
├── iscsid.conf
├── nodes
└── send_targets

3 directories, 3 files


[wintpe]

once you login it is supposed to become persistent

systemctl status open-iscsi.service

what errors are you getting from that re your login status.

regards peter

[magfan]

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# systemctl status open-iscsi.service
● open-iscsi.service - Open iSCSI Daemon
   Loaded: loaded (/usr/lib/systemd/system/open-iscsi.service; enabled; vendor preset: enabled)
   Active: active (running) since Do 2017-12-07 11:08:30 CET; 3h 38min ago
  Process: 2873 ExecStart=/sbin/iscsid (code=exited, status=0/SUCCESS)
  Process: 2829 ExecStartPre=/usr/sbin/modprobe -q iscsi_tcp (code=exited, status=0/SUCCESS)
   CGroup: /system.slice/open-iscsi.service
           ├─2875 /sbin/iscsid
           └─2876 /sbin/iscsid

Dez 07 11:08:30 thalamus_nfs systemd[1]: Starting Open iSCSI Daemon...
Dez 07 11:08:30 thalamus_nfs iscsid[2873]: iSCSI logger with pid=2875 started!
Dez 07 11:08:30 thalamus_nfs systemd[1]: Started Open iSCSI Daemon.
Dez 07 11:08:31 thalamus_nfs iscsid[2875]: transport class version 2.0-870. iscsid version 2.0-872
Dez 07 11:08:31 thalamus_nfs iscsid[2875]: iSCSI daemon with pid=2876 started!


I just found an article on the redhat customer knowledgebase which describes exactly my problem (iscsi, lvm, mount at boot). But without a subscription I cannot read it and I do not find another solution.

https://access.redhat.com/solutions/3889

[doktor5000]

But without a subscription I cannot read it and I do not find another solution.

It only mentions to mark those ISCSI target in fstab with the _netdev option:

Resolution
To mount iSCSI LUNs in /etc/fstab, add _netdev to the mount options near the end of the line. Properly formatted /etc/fstab lines for two different iSCSI mount points are shown below:
Raw
#device mount point FS Options Backup fsck
LABEL=data1 /mnt/data1 ext3 _netdev 0 0
LABEL=data2 /mnt/data2 ext3 _netdev 0 0
Note: If the file system being mounted exists directly on the device (i.e., does not use LVM), then the use of labels as in the example above is recommended. Device ordering may change each time the iSCSI devices are presented, and either LVM or labels can ensure that the correct device is mounted.
The netfs service also needs to be enabled at boot time, as it is responsible for mounting devices that use _netdev

Not sure about netfs service, if that is still required with systemd, but you can check the status of that, it doesn't hurt.

[jiml8]

But without a subscription I cannot read it and I do not find another solution.

It only mentions to mark those ISCSI target in fstab with the _netdev option:

Yes. Here is my fstab entry:

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# Entry for NAS iscsi extent :
LABEL=NAS1 /mnt/NAS ext4 relatime,noauto,nofail,_netdev,acl 1 2

[magfan]

Here is the entry in my /etc/fstab:

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/dev/vg_icebox/lv_imagepool    /imagepool      xfs     _netdev,rw,inode64,logbufs=8    1       2

The open-iscsi.service starts but that is all. It does not login into any portal and therefore it does not provide any device like /dev/sdb. This is why lvm cannot detect and activate any VG / LV and finally the desired lvm partition cannot be mounted. I guess there is a problem with my iscsi configuration.

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# iscsiadm -m discoverydb -t st -p 192.168.10.10:3260 -P 1 --discover
Target: iqn.2010-08.eu.n-tec:icebox-rix6r-000905600:dev0.ctr1
        Portal: 192.168.10.10:3260,0
                Iface Name: default
        Portal: 192.168.20.10:3260,0
                Iface Name: default
        Portal: 192.168.3.1:3260,1
                Iface Name: default
        Portal: 192.168.4.1:3260,1
                Iface Name: default


I want to use only Portal: 192.168.10.10:3260,0. How can I do this?

[magfan]

It seems to me I could solve the problem with a new systemd service (iscsi-login.service) which performs the missing tasks while booting:

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[Unit]
Description=Login into ISCSI portal
Requires=network.target open-iscsi.service
After=network.target open-iscsi.service

[Service]
Type=oneshot
RemainAfterExit=yes

ExecStart=/usr/sbin/iscsiadm --mode node --targetname iqn.2010-08.eu.n-tec:icebox-rix6r-000905600:dev0.ctr1 --portal 192.168.10.10:3260 --login
ExecStartPost=/usr/sbin/vgchange -a y

ExecStop=/usr/sbin/iscsiadm --mode node --targetname iqn.2010-08.eu.n-tec:icebox-rix6r-000905600:dev0.ctr1 --portal 192.168.10.10:3260 --logout

[Install]
WantedBy=multi-user.target