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 [ Total topics 33 Go to page 1, 2, 3, 4

Message
 Post subject: Cisco SSH error - Received disconnect from <IP>: 2: Protocol error: expected packet type 61,
PostPosted: Tue May 05, 2015 5:06 pm 
The following Cisco SSH error will be encountered after password is entered:
Code:
Received disconnect from 5.105.4.98: 2: Protocol error: expected packet type 61, got -1


To solve this, check the ssh login timeout which may be too aggressive for strong passwords:
Code:
#sh run | i ssh time
ip ssh time-out 5


In this case, if the password is not entered in 5 seconds, Cisco IOS ssh will disconnect the client.

Read more : Cisco SSH error - Received disconnect from <IP>: 2: Protocol error: expected packet type 61, | Views : 1281 | Replies : 0

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 Post subject: Linux: list block devices UUID
PostPosted: Tue Mar 10, 2015 5:46 pm 
Code:
root@ubuntu-vpsie:~# blkid
/dev/sr0: LABEL="Ubuntu 14.04.2 LTS amd64" TYPE="iso9660"
/dev/sda1: UUID="72a18500-a7fe-41cc-b7b6-72367439424a" TYPE="ext4"
/dev/sda5: UUID="8be2383f-aeb9-408a-933e-0cf62696f0d9" TYPE="swap"
root@ubuntu-vpsie:~# lsblk
NAME   MAJ:MIN RM   SIZE RO TYPE MOUNTPOINT
sda      8:0    0     8G  0 disk
├─sda1   8:1    0     7G  0 part /
├─sda2   8:2    0     1K  0 part
└─sda5   8:5    0  1022M  0 part [SWAP]
sr0     11:0    1   996M  0 rom  /media/andrei--ubuntu/Ubuntu 14.04.2 LTS amd64

Read more : Linux: list block devices UUID | Views : 711 | Replies : 0

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 Post subject: Linux: List kernel supported filesystems
PostPosted: Tue Mar 10, 2015 5:45 pm 
Quote:
ESCRIPTION
When, as is customary, the proc filesystem is mounted on /proc, you can find in the file /proc/filesystems which filesystems your kernel
currently supports. If you need a currently unsupported one, insert the corresponding module or recompile the kernel.


root@ubuntu-vpsie:~# cat /proc/filesystems
nodev sysfs
nodev rootfs
nodev ramfs
nodev bdev
nodev proc
nodev cgroup
nodev cpuset
nodev tmpfs
nodev devtmpfs
nodev debugfs
nodev securityfs
nodev sockfs
nodev pipefs
nodev devpts
ext3
ext2
ext4
nodev ...

Read more : Linux: List kernel supported filesystems | Views : 409 | Replies : 0

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 Post subject: Rsync progress display during transfer
PostPosted: Tue Mar 03, 2015 8:24 am 
Rsync is a powerful tool to transfer files from one server to another or from one directory to another. To enable progress display while you transfer a file use the --progress switch (double dash).
Quote:
--progress show progress during transfer



Example how to use rsync progress display


Code:
$ rsync --progress source:/tmp/file .
file
      2,359,296   0%    1.07MB/s    0:14:39 


---------
Syncronizing directories from a remote directory to local directory or vice-versa can be done using rsync. ...

Read more : Rsync progress display during transfer | Views : 13658 | Replies : 2

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 Post subject: Linux clear screen / terminal
PostPosted: Tue Mar 03, 2015 8:20 am 
Linux clear screen terminal and move the shell prompt to the top of the screen.

Linux terminal can get filled with a lot of text if you use cat instead of less or more or if you are grepping a file for a pattern that is very loose.

Also, if you login via a serial console and the shell prompt gets moved in the middle of the screen overlapping with previous boot screen messages.

Clear ...

Read more : Linux clear screen / terminal | Views : 4371 | Replies : 2

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 Post subject: FreeBSD quickfix: Shared object "libpcre.so.1" not found, required by "nginx"
PostPosted: Mon Feb 09, 2015 4:55 pm 
Following error occurs when executing nginx in FreeBSD:
Code:
Shared object "libpcre.so.1" not found, required by "nginx"

This requires "pcre" package to be installed:
Code:
$ pkg install pcre

Read more : FreeBSD quickfix: Shared object "libpcre.so.1" not found, required by "nginx" | Views : 1544 | Replies : 0

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 Post subject: Checking Linux virtual memory page size
PostPosted: Mon Feb 09, 2015 4:53 pm 
Linux kernel virtual memory model is paged. This means the virtual memory space is divided into small units called “pages”, to quote wikipedia: “blocks of contiguous virtual memory addresses”.

To query configuration of the Linux virtual memory, use “getconf” utility:
Code:
$ getconf -a | grep PAGE
PAGESIZE                           4096
PAGE_SIZE                          4096


The amount is expressed in bytes.

Read more : Checking Linux virtual memory page size | Views : 417 | Replies : 0

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 Post subject: How to list the largest files in a directory in Linux/FreeBSD
PostPosted: Thu Jan 22, 2015 5:14 pm 
One of the first things to do when cleaning up a filesystem is finding old, large and no longer necessary files.

Usually on Linux and Mac laptops, directories such as “Downloads” tend to become very large in time. Old installers and archives are the first ones at eating filesystem space.

How to list all files in current directory and sort them by their size.


For files it is enough to use the “ls” command. Either ...

Read more : How to list the largest files in a directory in Linux/FreeBSD | Views : 487 | Replies : 0

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 Post subject: GPG key retrieval failed: [Errno 5] OSError: [Errno 2] No such file or directory: '/etc/pki/rpm-gpg/
PostPosted: Tue Jan 20, 2015 4:15 am 
GPG key retrieval failed: OSError: No such file or directory: '/etc/pki/rpm-gpg/RPM-GPG-KEY-EPEL'

This fix requires fetching the GPG key from fedora website:
Code:
# cd /etc/pki/rpm-gpg
# wget --no-check-certificate https://dl.fedoraproject.org/pub/epel/RPM-GPG-KEY-EPEL

Read more : GPG key retrieval failed: [Errno 5] OSError: [Errno 2] No such file or directory: '/etc/pki/rpm-gpg/ | Views : 1185 | Replies : 0

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 Post subject: FreeBSD - list disks drive in the system with atacontrol and camcontrol
PostPosted: Tue Jan 20, 2015 3:08 am 
FreeBSD uses ad prefix for IDE/SATA disks and da prefix for SCSI and other technologies disks.

ad ATAPI (IDE) disk
da SCSI direct access disk
acd ATAPI (IDE) CDROM
cd SCSI CDROM
fd Floppy disk
A snapshot of all the information and hardware detected by the kernel at boot time is kept in /var/run/dmesg.boot file.

List all hard disk drives installed into FreeBSD and detected by kernel using atacontrol



# egrep '^ad[0-9]|^da[0-9]' /var/run/dmesg.boot
ad0: ...

Read more : FreeBSD - list disks drive in the system with atacontrol and camcontrol | Views : 6680 | Replies : 0

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 [ Total topics 33 Go to page 1, 2, 3, 4


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