Checking your outgoing mail server (Is Port 25 blocked?)
Many email clients and services use port 25 for SMTP to send out emails. However an ISP (Internet Service Provider) may block port 25 in order to prevent spamming by its customers. Here is how you can check to see if port 25 is blocked on your network.
1. Type the following command:
telnet serverbuddies.com 25
2. View Results:
If port 25 is not blocked you will get a successful 220 response (text may vary).
telnet serverbuddies.com 25
Trying 67.228.43.85…
Connected to serverbuddies.com.
Escape character is ‘^]’.
220-box.serverbuddies.com ESMTP Exim 4.69 #1 Mon, 07 Jun 2010 02:23:15 -0500
220-We do not authorize the use of this system to transport unsolicited,
220 and/or bulk e-mail.
If port 25 is blocked you will get a connection error or no response at all.
Trying 67.228.43.85…
telnet: connect to address 67.228.43.85: Connection refused
telnet: Unable to connect to remote host
Installing the PEAR package manager and Checking if PEAR works
When using PHP >= 4.3.0, the PEAR Package Manager is already installed unless one has used the ./configure option –without-pear.
Verifying command line tool
Both pear and pecl tools should be available everywhere on command line. For that to work, pear’s binary (bin) directory should be in your PATH variable.
# apt-cache search php-pear
php-xml-util – a XML utility for php-pear
php-pear – PEAR – PHP Extension and Application Repository
To verify it works, simply type pear. A list of commands should be shown:
root@laptop:~# pear
Commands:
build Build an Extension From C Source
bundle Unpacks a Pecl Package
channel-add Add a Channel
You should further test that PEAR is up to date:
root@laptop:~# pear version
PEAR Version: 1.7.1
PHP Version: 5.2.6-3ubuntu4.5
Zend Engine Version: 2.2.0
Checking mysql extended-status
mysqladmin is a client for performing administrative operations. You can use it to check the server’s configuration and current status, to create and drop databases, and more.
root@dell:~# mysqladmin status -uroot -p
Enter password:
Uptime: 197 Threads: 1 Questions: 135 Slow queries: 0 Opens: 40 Flush tables: 1 Open tables: 34 Queries per second avg: 0.685
For Extended Status
root@dell:~# mysqladmin extended-status -uroot -p
Checking Postfix file permission/ownership discrepancies
The first line (postfix check) causes Postfix to report file permission/ownership discrepancies.
# egrep ‘(reject|warning|error|fatal|panic):’ /var/log/maillog
The second line looks for problem reports from the mail software, and reports how effective the relay and junk mail access blocks are. This may produce a lot of output. You will want to apply some postprocessing to eliminate uninteresting information.
Checking system default VM setting using sysctl
Some of the VM settings for the kernel can be changed using sysctl. Here is a listing of the default settings for a system on 2.6.27
root@dell:~# sysctl -a |grep vm
vm.overcommit_memory = 0
vm.panic_on_oom = 0
vm.oom_kill_allocating_task = 0
vm.oom_dump_tasks = 0
vm.overcommit_ratio = 50
vm.page-cluster = 3
vm.dirty_background_ratio = 10
vm.dirty_ratio = 40
vm.dirty_writeback_centisecs = 499
vm.dirty_expire_centisecs = 2999
vm.nr_pdflush_threads = 2
vm.swappiness = 60
vm.nr_hugepages = 0
vm.hugetlb_shm_group = 0
vm.hugepages_treat_as_movable = 0
vm.nr_overcommit_hugepages = 0
vm.lowmem_reserve_ratio = 256 32 32
vm.drop_caches = 0
vm.min_free_kbytes = 2033
vm.percpu_pagelist_fraction = 0
vm.max_map_count = 65536
vm.laptop_mode = 0
vm.block_dump = 0
vm.vfs_cache_pressure = 100
vm.legacy_va_layout = 0
vm.stat_interval = 1
vm.mmap_min_addr = 0
vm.vdso_enabled = 2
vm.highmem_is_dirtyable = 0
